We’ve migrated the Perelman’s Cigarcyclopedia to Windows Phone 7, it is available here (US) and here (UK). We have it available for iPhone, Android and Blackberry already, we thought of trying out the Marketplace and the development ecosystem.
For an experienced Microsoft developer the development and debugging are easy, the learning curve is quite small. Compared to the other platforms we found it very easy to develop and submit to Marketplace. We received very informative feedback from the testing team (seeing the level of feedback we assume at least some tests are manual) and after some small fixes it was up in the Marketplace.
If you have an app that you want developed or migrated to Windows Phone 7, contact us here.