With the Windows Phone 7 event creeping up tomorrow, it's likely we'll see leaks ahead of the events worldwide. We're expecting to see a multitude of features unveiled and to be finding out the final release date of the major update to the platform.
Good news for developers, however. Neowin can today confirm from independent sources that the Windows Phone "7.5" SDK will likely be made available at some point tomorrow, likely alongside the UK/US unveiling of the consumer based features. The tools will be in Beta for now, according to one source. We've also heard from another source that the tools won't be released tomorrow, but in the next few days instead.
We're also hearing that this announcement around Mango will not be a "preview" of the final platform, but instead the OS will be announced as RTM tomorrow (release to manufacturing), and that the update will be available via carriers as soon as September.
Finally, we're also hearing whispers that Microsoft will announce a invite only based "preview program" of Mango for developers that will either allow them access to test devices or let them flash their own phones with a release of Mango.
Neowin will be covering the Mango event live tomorrow from the London and New Zealand events, so make sure to bookmark this page. We also have a comprehensive list of what we expect Microsoft to announce at the event, but we're hearing there is much, much more than what we've already seen.
Update: When we say "September release," we're hearing that Microsoft will release it to all carriers before then and plans on attempting some sort of unified release. Also, we're hearing that WP7 won't RTM, but is indeed "feature complete" in the state it is in now, and that testing will now begin to be under way.