You do need to now set up an account (my.avast.com) in order to register. It's acknowledged by VLK, avast service manager, in a post (#383) over at Wilders in the thread announcing the new version of avast. I can't post a link to Wilders because I don't have enough posts, but you can feel free to go there and check it out. Also, the old registration required a name and an email. The new registration requires a password and the above-noted Captcha.
Thanks. And no doubt about it -- the key is to find the balance between security and real world workability. I haven't added too many programs since removing Avast and installing MSE, so I can't attest to the way MSE handles installations. But I do remember that frequently I'd have to either disable Avast, or click through a lot of "Allow/Add to Trusted Program" screens when installing programs with Avast 6 running. And maybe that's a good feature, I don't know. I do know that I disabled UAC in Win 7 because that just became way too much of a PITA. EVERY time I tried to run an already installed program I got a message, and there was no way to "teach" UAC what was trusted and what was not. But hey...that's just me.