@figuerres: SQL Azure has its own replication strategy to ensure no data loss but when it comes to making a backup at a certain point in time it does not have that capability like we would do in SQL Server.  So say your user is about to perform a significant function in your system and you would typically auto-generate a backup prior to this operation for the user's safety as an example.  In SQL Azure you have to make a copy of the database then bacpac export that copy to Azure storage.  The reason you have to make a copy of the database is because SQL Azure provides a transactionally consistent set of data in the database copy that you would not get if making a bacpac directly from the live database.

EDIT: worth a mention, the exporting of the bacpac of that 2.7 GB database to Azure storage took 1 Hour and 13 minutes on top of the 25 minutes waiting for the database copy.  (important detail: all in the same datacenter)