The Windows Phone 7 launch has mostly gone off with few if any hitches for developers, but there will always be something bothering them and in this case, it appears to be a legitimate concern.
Two developers, Justin James and Nicholas Yu (the latter making GoVoice) have noted that they won't receive payments for their apps till February, which is quite far off especially if like Yu, your app launched with Windows Phone 7. Going further, the developers complain that there are no analytics to measure how popular their app is--in other words, they don't know how many they have sold.
For Yu and his GoVoice app, this is important because he wants to add the much coveted Push Notifications to his app (he already began rolling it out last week). But without knowing how many apps he has sold, nor receiving payment till February, he has to pay the server costs upfront and basically hope that he can recoup the costs. Hardly an ideal position for a developer to be in. James concludes that for now, developers should consider WP7 a hobby instead of a source of revenue. Ouch.
Microsoft is known for treating developers pretty well--better than Apple and even Google--so we hope that they can at least address this issue before others start to feel the same way. On the other hand, these growing pains are to be expected for such a new platform--the test is to see how it is resolved.
Further reading: Arktronic