About 6M people have already signed up to BBM.com get more details, so in theory they should all get an immediate access. Here is the general process to get access if you don’t have access now:
Just download the app, and register with your email. At that point, you will get in the virtual line to have access. Right now, it’s not clear how long it will take, but Blackberry says that its engineers are working around the clock to get everyone on board. When the app was initially leaked, there was no big technical issues, so maybe this is just an abundance of caution. We’ll see.
BlackBerry has added a note for users from Sub-Sahara Africa, in case you read this from there: “Samsung customers in Sub-Sahara Africa can download BBM today from the Samsung Apps store. iPhone and other Android users in Africa will be able to download the app in three days’ time” [BB blog post]