The way I understand it, if you want to leave an identified comment that links back to your own blog or profile, it's not necessary to have a Google account - you should be able to use any OpenID, including your Wordpress or Typepad ID, for your folks who blog on one of those platforms. Just sign in with that ID when you comment:
The drop-down menu for Sign-in will give you your options. The "nickname" option will let you leave a name, but no link, with your comment. (You could be anonymous if you want to, but I hope you won't.)
Thanks to Working Girl (a non-Googler) for asking the question that gave me a heads-up about the change, and to the very useful Google Operating System for the scoop.
(And speaking of changes in commenting procedures, have you noticed the recent option to be e-mailed with follow-up comments? It can save you time checking back for responses, but it could also send you a lot more e-mail, since it sends you all subsequent comments, not just those from the blog author. That could keep your Inbox very busy when you're on of the early "good cooperations" - this post has 51 so far - on a Bub and Pie post. The option works on a per-post basis, though, so you can pick and choose which posts you want to follow. Literary Feline says she's taken a liking to it.)