Later today at Twitter’s Chirp conference in San Francisco, BoomTown is moderating a panel titled “Investing in the Ecosystem.”

Or as I like to call it, “How Do You VCs Come Up With Those Crazy Valuations: Magic 8 Ball? Ouiji Board? Darts?”

I have a choice group of dudes–of course, they are all dudes–for the panel, all of whom have invested in a range of start-ups, including Twitter.

They include: Polaris Ventures’ Mike Hirshland, Venrock’s David Pakman, Bijan Sabet of Spark Capital, and Benchmark Capital’s Peter Fenton.

Presumably, the group of venture capitalists will give the audience the 411 on what goes into finding, feeding and nurturing the many innovative start-ups that populate the Twitterverse.

That is, until you actually try to compete with Twitter or make some dough without its sanction, wherein all the nice Whos-down-in-Whoville sweetness of the folks who run Twitter turns into the backroom at the Bada Bing with Tony Soprano and the boys.

(You can see Twitter COO Dick Costolo here, in fact, giving us his best Don Corleone in this video interview with MediaMemo’s Peter Kafka.)

The tensions of late between Twitter and the many third-party developers circling it are perhaps going to add some frisson to the two-day event at the Palace of Fine Arts, which costs $469 to attend. Twitter also just announced its advertising platform plan.

The first day is all talk, from Costolo, Twitter CEO and co-founder Evan Williams, co-founder Biz Stone and others. The second day is 24-hour hackathon.

For those not there, Twitter will be streaming the event live with the help of Justin.tv.

And, of course, there will be tweets–lots and lots of tweets.

[Sticker image courtesy of Zazzle.com]

Yesterday, BoomTown wished Carol Bartz a happy one-year anniversary as CEO of Yahoo.

And today, it is time to shamelessly judge her tenure!

As I noted, in an interview with Bloomberg last week, Bartz gave herself a “B-minus in her first year.”

In the Bloomberg interview, Bartz explained that she gave herself a B- because she should have moved faster to reorganize Yahoo (YHOO) and to strike an online advertising and search partnership with Microsoft (MSFT), even as she noted that the management challenge at Yahoo “was a little tougher internally than I think I had anticipated.”

But an overall grade is too easy! Instead, over the next days, it’s time to drill down on specifics: Management, financials, product innovation, deal-making and, yes, moxie.

And for management, I give Bartz an A-.

Here’s why:

Pros: There is no question that the hard-talking Bartz took charge from the get-go, expertly grabbing the reins at Yahoo and hitting targets on her very first day like some kind of digital Annie Oakley.

At her memorable press conference on Jan. 13, 2009–lasting only 15 minutes and three questions–Bartz sternly admonished everyone to give Yahoo some “friggin’ breathing room” and noted that the company “frankly, could use a little management.”

It was a refreshing statement of the obvious, especially after the tough year suffered by outgoing CEO and co-founder Jerry Yang, who was pretty spent by the end of his tenure.

Thus, any leader who had any kind of kinetic energy was going to get noticed.

And Bartz? She is–and I mean this in the nicest way–a nuclear reactor set to high.

At the press conference, Bartz also described herself a “straight shooter.”

Finally, she said she thought it “nonsense” to think that Yahoo was not feeling great about itself, spitting out the word “nonsense” in that scary-mommy, end-of-discussion way, like someone who has kids and knows a thing or two about nonsense.

And, I would have to say, Bartz has pretty much kept up the necessary take-charge tone and followed it up with action.

She has projected firm leadership internally and to Wall Street, made cuts in staff immediately and restructured her top management quickly, rendered fast decisions about cutting or selling off the hairball units at Yahoo, and struck key partnerships with Microsoft (MSFT) and Facebook.

And she has done so with little of the sentimentality that had long characterized Yahoo, going out of her way to tell people what she thought rather than doing the typical “Kumbaya” moves.

If her success in management could be boiled down, its essence would be this: Carol knows how to clean up a troubled company, Carol knows how to take charge and most of all, Carol makes decisions.

Cons: And that’s just where the minus comes in.

From the start and still today, I have heard many at Yahoo grumble that while Bartz has a terrific ability to make decisions, she might be too much about decisive decision-making than about making good decisions.

To be fair, that’s exactly what people who avoid making tough decisions always say.

Still, the worry about this has persisted, with many calling Bartz’s manner more showy than substantive, more brute force than finesse. Her tough style–especially when she starts to curse–definitely grates some.

There is obviously a whiff of sexism here–which any strong-speaking woman in tech is subject to and must find a way to completely ignore.

It is hard to do. Thus, I have heard Bartz negatively called by employees: Sarah Palin of the Internet (Maverick!), Al Haig of the Internet (I’m in charge here!) and Tony Soprano of the Internet (Badda Bing!).

Externally, while she has a lot of prominent supporters in Silicon Valley, more than enough major Internet execs have asked me sotto voce if the former Autodesk (ADSK) CEO knows enough about the Internet business–and not just software and tech, where she has loads of experience–to be an effective leader (I will get to that when I grade product innovation).

What’s interesting here is that for all those who don’t like her style, she also garners a rabid fan base at Yahoo and among investors, who are very glad someone is projecting leadership and putting the ducks in order at the company.

The bottom line, though, is that Bartz does not seem to care all that much about what anyone thinks of her.

On her first day, she said: “My focus is on turning the company around.”

And in this regard, she has most definitely kept that focus and that promise.

Of course, all of this depends on how Yahoo recovers financially and how its stock performs on Wall Street, which will be the next area to be graded.

As most know by now, Microsoft CEO Steve Ballmer introduced the software giant’s relaunch of its search offering, dubbed Bing, onstage at the seventh D: All Things Digital conference.

You can see that here, as well as Ballmer demoing the product, which is Microsoft’s biggest and priciest attempt yet to catch archrival Google (GOOG) and Yahoo (YHOO) in the search business.

It is a market where the typically dominant Microsoft (MSFT) is a mouse in comparison, although it is also trying to innovate.

That did not stop Ballmer from doing some roaring about Bing, in an interview with Walt Mossberg, as well as the status of other Microsoft products like its upcoming release of the Windows 7 operating system, an arena where Microsoft does rule.

Ballmer also talked about ongoing talks with Yahoo about a search partnership, and other Microsoft initiatives.

Here’s the video of Ballmer’s full D7 session (this video is missing a promotional video for Bing, which the audience saw, but that Microsoft did not give us video rights to use here):