Ich zitiere auch mal Microsoft zum Thema WP 7.8 update
The new Start screen is so useful and emblematic of what Windows Phone is about that we want everybody to enjoy it. So we’ll be delivering it to existing phones as a software update sometime after Window Phone 8 is released. Let me repeat: If you currently own a Windows Phone 7.5 handset, Microsoft is planning to release an update with the new Windows Phone 8 Start screen. We’re calling it “Windows Phone 7.8.”
Some of you have been wondering, “Will we also get Windows Phone 8 as an update?” The answer, unfortunately, is no.
Windows Phone 8 is a generation shift in technology, which means that it will not run on existing hardware. BUT we care deeply about our existing customers and want to keep their phones fresh, so we’re providing the new Start screen in this new update.
Als Lumia 900 Nutzer würde ich spätestens jetzt einen Brechreiz bekommen, weil so wie es aussieht gibt es ausser dem neuen Startscreen sonst keine Features