Got this upgrade notification in AppWorld yesterday, installed it and BBM completely gone. Followed all the recommended RIM fixes, checked if hidden, installed from the website, i even did a full security wipe and re-installed the upgrade and still gone.
I spoke to someone at RIM and was told i have to give my Blackberry in for a software re-installation (6 weeks of inconvenience). My BBM was working just fine before this upgrade came along. I wonder how many thousands of people (looks like many on the reviews) have to sit without a cell phone because of having to send their BB's in for software re-installations....... Is there a way of installing my previous BBM version ? think it was 6.0.0.129....

Where are you seeing the reviews where others are having this same issue?

I can see Blackberry Messenger in app world as installed, this is where the reviews are I refer to. The icon is nowhere to be found on my BB.

okay .. this might help you out. you don't have to go for BB centre. hope your BB is unlocked.

just wipe your BB with JL_Cmder, then load the software thru app loader.

if you need more help, you may PM me... will help you out.