I am running WinXP SP2 Pro.
When I upgraded from Comodo 3.9.95478.509 to the next release, everything I had blocked now had free access to the Internet.
Before I upgraded from Internet Explorer 6 to Internet Explorer 7, I had Windows Explorer blocked from all access to the internet. (This was due to a hidden executable / trojan that had run on my computer once that used used Windows Explorer to FTP some unknown file to someplace in Eastern Europe). Since I never use Windows Explorer to get on the Internet, it was fine for me to block all internet access - and it also provided a useful tool to check if Comodo was working properly after an update. (Note: The Windows Explorer test doesn't work after I upgraded to IE7, since now Windows Explorer will automatically start up IE7 when a URL is entered into the path field in Windows Explorer).
I also had Adobe_Updater blocked, and it wasn't blocked after upgrading.
It has been a few months since I "downgraded" Comodo back to 3.9.95478.509 (for me it was an upgrade). I'm not sure, but I think that the "Settings >> Update >> Automatically perform an online lookup" option is no longer available after that update (or maybe it isn't working).