There's plenty of excitement surrounding the release of Windows 8 here at Build. The general consensus around the operating system, however, holds that the key to the OS's success is all about the apps, and CEO Steve Ballmer had no shortage of news on that front. The green-polo-shirted exec made mention of an official tweet from Twitter, noting the service's development plans for a Windows 8 app coming "in the months ahead." Also on the slate is Dropbox -- the popular storage service has an app "coming soon," according to Microsoft's own official blog. ESPN got a little face time at the event, showing of