Well, we were almost right. We said BBM was arriving imminently, but we were wrong about the exclusive part.BlackBerry has put things straight by announcing that BBM will be available for Android phones on Saturday (21 September), with an iOS app to follow on Sunday (22 September). It means that the BBM network will suddenly explode over the weekend. That's a good thing for BlackBerry in terms of device reach, but you do wonder if it will have an impact on BlackBerry sales. Which aren't exactly through the roof right now.The cross-platform app will offer what the existing BBM does, which is instant messaging and group chat, only this time, it will be with a potentially much larger group of friends.That's just the first step though, with voice calls and video chat to follow further down the line. There is also talk of BBM becoming a separate company, with separate investment heading to the platform and more new products likely, including even more reach via BBM desktop.All of that in the distant future. In the near future, you can get those apps in a matter of days.