5.5 looks really good so far...

I have found that it handles our ESX VMs very well (as in they are all within the correct groups). The Power/performance monitoring is working great though it can be a little slow to return the summary information when a server is highlighted. Software updates, alerts and more or less everything else, including repository updates etc is working fine. It may just be my environment, but I also feel it is using slightly less server resources as well...

Thanks,
Stuart.