“We’re still in the early stages,” Microsoft Senior Product Manager Greg Sullivan told Mobilized in a phone interview on Wednesday. “When people use this phone, they really, really like it.”

Back in December, Microsoft said that 1.5 million Windows Phone 7 devices had shipped to carriers.

AT&T, which carries the broadest lineup of Windows Phone 7 models among the U.S. carriers, declined to give out specific sales figures, but said that sales have been steadily growing since launch and that 90 percent of customers said they would recommend a Windows Phone to others.

“We believe this shows that Windows Phone has a bright future in an intensively competitive space,” an AT&T spokesman told Mobilized.

LG had less-nice things to say, with an executive telling a mobile enthusiast site that early sales weren’t what it had hoped. “From an industry perspective we had a high expectation, but from a consumer point of view the visibility is less than we expected,” LG’s James Choi told Pocket-lint.

Sales are an important measure of success over the long term, but perhaps not even the best indicator of the platform’s long-term success, Sullivan said.

“One of the key ways that we’ll measure success of Windows Phone is did we ship a phone people love,” he said, pointing to its customer-satisfaction data, which said that 93 percent of early customers are “satisfied” or “very satisfied,” adding, “That’s a really great number.”

Not the sort of proclamation you’d expect from a Blu-ray backer, but then, Samsung’s always been one to hedge its bets. For a time, the company backed both horses in the next-generation DVD race, launching a dual-format high-definition DVD player that supported both HD-DVD and Blu-ray Disc.

So what’s Samsung hedging its bet on this time? OLED displays, according to Griffiths. Which presumably means the company sees HD streaming video and low-cost holographic storage hitting the mainstream sooner than you might think.