We were hoping to have all our questions answered about Windows Phone Marketplace today - especially since it's clearer than ever that Marketplace is really going to be the only way for consumers to get apps on their device. We know a bit more than we did before, but "We'll tell you at MIX" has been replaced with "We'll release more details in May" for many of the essentials.

We do have a few more details - we'll drop those and some images from the presentation after the break!

 

What we do know is that Microsoft is pushing hard for developers to use their Trial system to promote apps. It's a benefit to be sure as it means there's a single entry for each app (and thus a higher download count). While the trial functionality looks fairly robust, there are going to be plenty of other missing features at launch, including subscription models, in-app purchases, the ability to charge for significant upgrades, and parental controls. On the bright side, apps are associated with your Live ID and can be installed on up to five Windows Phones.

Strangely, while Microsoft has been touting the integration with Xbox Live, it doesn't look you'll be able to buy an app on the Xbox and have it magically appear on your Windows Phone or vise versa.

Praise be: There will be a single, simple "Update all" option within Marketplace.

For developers, Microsoft let loose that they're going to be acceping app submissions "later this summer," but they encourage devs to drop the $99 to register now and to download the free dev tools. Interestingly, Windows Phone devices will need to call home to Microsoft to get "unlocked for a period of time" before developers will be able to sideload their own apps onto devices for testing. Microsoft is doing their level best to lock down any sort of file system access either directly on the phone (apps will get their own sandboxed space) or via USB.

The big question we're waiting until May for? The exact details on what Microsoft will block from the Marketplace. Microsoft directs developers to their current guidelines for the 6.5 verssion which will be updated in May but shouldn't radically change. Also coming in May: more details on Microsoft's plans for in-app purchases, subscription models, and other business models for apps.