Before release of this milestone, the software has undergone extensive testing – in daily use by more than 1000 people at Microsoft who have been using WP7 as their only phone for the past several months, and the more than 10,000 devices in our test labs. We’ve been testing usability, battery life, network connectivity, and many other metrics for a long time. As a result of that work, I hope you will find the experience to be of surprisingly high quality…
"[A]fter using it as my primary device for five days I have yet to see ANY lockups, freezes, or resets on the Samsung device I am testing out," says Matthew Miller, at ZDNet.com. "Actually, I am blown away by how stable this version of the software is because I have seen more issues with shipping devices running the iOS, Google Android OS, etc. than I have with this version of the software."
Welcome back into the smartphone arena Microsoft, it looks like you have a serious challenger entering the ring and I will definitely be purchasing a device as soon as I can…
It’s crunch time for the Softies. They have developed a new phone platform from scratch that looks and feels different from what’s available from Apple, Android backers and RIM. They’ve built it, but will developers come? Microsoft is counting on its developer tools, its developer outreach programs and developer guarantees (in the form of payments if WP7 apps don’t sell as well as expected) to generate quantity and quality WP7 apps.
Windows Phone Developer Blog