I have a small install. 9 BB, BES 4 SP4 running all services on one serer with the MSDE database.

The geek in me wants to upgrade to 4.1. The responsible IT manager in me doesn't want to take the chance.

Is the upgrade still risky (tinking of an in-place upgrade), and do the benefits outweigh the risks?

Im on the fence too. I see only a few MAJOR benefits to upgrading and I am not sure if its worth the risk.

My BES server has been bullet-proof since I installed HotFix#2 over my SP4 - so I keep asking myself - "why mess with it"?

I'd wait until 4.1 SP1. The MDS install problems should be fixed by then, which seem to be what many people (including myself) have gotten stuck on. A lot of what's in 4.1 looks wonderful for managing a large number of handhelds (dozens or hundreds).

I've been playing with a copy in my test environment for a couple of days. It certainly has a more Active Directory feel to it with the group structures, and as phonemonkey says, a big benefit for large organisations. I have not noticed any issues yet - nice simple install and deploying a few test devices was faultless. I'm intending a full in house rollout to our main BES servers next week pending a few more tests. I'm definitely interested in hearing more about these 'MDS install problems'.