Microsoft has another planned big announcement for June 20. The company is flying out to San Francisco for what will be a two day developers summit.

One such surprise, which is generating a lot of eleventh-hour excitement, is the anticipated Windows Phone 8. So far, here's what we know from around the web:

Codename: Apollo (or Windows Phone 8)

Upgrade: Multi-core processors (a step up from the single core units used in handsets like the Lumia)

Update: Windows NT core OS (rather than the outmoded Windows CE platform used in the Windows Phone 7)

Stay tuned for more updates.