As far as I know, it auto-updated during installation to the newest version.
I'm having a little trouble using it. I ran into a trojaned site from a google search about overclocked Q9550s, and it gave me those dialog boxes about my system being infected by malware, and please click here for a scan. So I clicked (being fairly well protected, not by my AV but by a limited user account and SRP, on XP Pro SP3), and it brought up a web page that looked like my C: in Windows explorer, and it started faking the scan, and then it popped up a dialog box that looked like a windows security dialog box, but of course it wasn't, and then clicking anything on the dialog resulted in the fake av .exe file being attempted to download. At this point my AV popped up and said something. But it didn't give me any real options to click on, so I figured it was handling it automatically.
It recently, a few days later, popped up a dialog and had a log screen, which I reviewed.
It contained five entries. Here's what's strange - they are listed as "Ignore Success", and virus type "Cryp_Krap-9". I certainly didn't click anything to "ignore" them. I do remember seeing something about the AV being unable to delete them outright when they were encountered.
Oh, and to get out of the malware fake scanning, I just End-Task'ed the browser, and deleted my temp internet files.
But it's a little disconcering that the AV couldn't delete the malware file, and it then later claimed that I chose to ignore it, when I made no such decision.
As far as I know, though, this machine isn't infected at all, thanks to SRP and LUA.