10,000 apps. An impressively broad ecosystem for just under five months of development. Apple’s (AAPL) year-end list of Top App Store Downloads for 2008, then, is both handy and timely (Click on the image below to see the top 10 paid and free apps). It’s largely what you’d expect, with the Games and Entertainment categories proving most popular, Facebook and Pandora dominating the Free App category, and Texas Hold ‘Em and Moto Chaser topping the Paid App category. Fascinating to see the breadth on display here. Were you to purchase every app currently for sale at the store, it would set you back in excess of $30,000.

Since I posted an interview with Social Gaming Network’s Shervin Pishevar today on the announcement of his $15 million funding, it seems only sporting to post this lively video interview I also did with his main competitor, Mark Pincus of Zynga, recently too.

Zynga, named after Pincus’s dog, is one of the two main social-gaming networks that are competing for audience by offering highly interactive games of all kinds. Its aim is to be more engaging and create a series of addictive games that users will return to again and again.

Pincus, who also founded the Tribe social-networking site, is a longtime entrepreneur. I met him way back when as a reporter at the Washington Post when he and Sunil Paul launched one of the few start-ups–Freeloader–in the D.C. area.

And I can report that Pincus is as jumpy and energetic today as he was 15 years ago.

He has certainly been busy lining up a spate of fancy investors, garnering $10 million in funding in January, including from: Union Square Ventures, Foundry Group, Avalon Ventures, Pilot Group, along with personal investments from Silicon Valley players Reid Hoffman and Peter Thiel.

Zynga, which is larger than rival SGN, claims 2.3 million total daily active users across Facebook, with its Texas Hold’em game being the largest it offers. Other games include Sea Wars, Blackjack, Attack! and Scramble.

As I said in my SGN post, while BoomTown often makes fun of viral apps, most of which are faddish and juvenile, the better-made gaming apps actually are likely to be a real business over time, as long they remain engaging and fun to play as the classic real-life games are.

Zynga plans on making money through ads, including creating its own ad network for other gamers, as well as via the sale of virtual goods and premium offerings.

Here’s a chat with Pincus at Zynga’s offices (Pincus owns the building, by the way, which also houses a bunch of other Web 2.0 start-ups) in San Francisco: