We are running a mixture of anyconnect 2.4 and 2.5 clients in the enterprise and we are looking at upgrading. I wanted to see if anyone could lend some advice on a staggered upgrade process? I would like to roll out the latest client to maybe 50-100 users to verify its compatibility. Ultimately, we will roll it out to about 10,000 users and stores. Our ASA's are running 8.2x if that matters? Thanks
Do you have a software distribution system in place already? Something like LANdesk or SMS.
You could push out the new clients via that method most easily. Then once you've passed the test phase, use the same thing to push to everyone. Or at that point you could also put the new images on your ASA and setup the profiles to download on connect. I'd prefer the former so as to use the best tool for the process.
A lot depends on your existing setup, both technical and organizational.
I'm not aware of any particular showstoppers with AnyConnect 3.0. The UI is completely reworked and looks much more modern. Of course it has a huge number of new capabilities as well. (There are licensing requirements to avail yourself of many of them though.) As a 1-1 replacement of your old client using the same features though it should be relatively straightforward.
I'd recommend you at least skim the AnyConnect Admin Guide (especially the chapter on deploying) and then first deploy to an even smaller group of IT / network staff before beginning your 50-100 user trial.