I'm just happy with the option of being able to use an avatar, and I have numerous public domain cliparts and photos at my fingertips to use, so username icons wouldn't be a pressing issue. However, I'll admit that if such a feature were added, it might be cute.

You can upload any image you want as an avatar image.  Note that square images work best as avatars.

Lightsaber? 

UPDATE: Just so you all know, my little avatar is really me and the whack little orb thing was done by X...

Even better, have RIA programmed to provide you with an icon depending on say, the predominant theme of your last 100 reviews or listings. 

A baseball for oscar, for example, or a lightsaber for numbah, a movie screen for m.a.duran, or a bucket of gorilla vomit for that guy who created the "disgusting list" last week.....

Well... ok...but then you'd get some idiot with a very garbled understanding of the multiple meanings of the word icon who would interpret it as something to be smashed who would then hit his or her own computer screen with a hammer...

No thank you. Generally icons from a list don't give you a very good selection, and it's bad enough having "[Insert Name Here]&hearts" on MySpace and every other website, but I like to think that good old RateItAll is too formal.
Also, if it means selecting an avatar, it will just slow down the website even more, which is something it really doesn't need...

I worry it would slow down the site still further. I've gotten to know most reviewers' names anyway, and don't need an icon to recognize them.

This would have my vote.  I've seen this on other forums; it really goes over well.

That would be sweet.

Add it.

A cute addition like they have on AOL

I like the idea. It adds more flavor and life to the page, which in turn stirs your mind, which in turn causes people to write more good opinions. Plus, it's fun to represent yourself in an artistic way. It would be even better if you could make your own avatar as well as being able to choose one.

We already have the ability to add a picture icon on our User Page. Many of us choose to add our own digital photo in this square, while a few others have preferred to be represented by some kind of icon that they might have borrowed from an internet page (just right click the pic, then Save picture as...). If some generic icons were made available for selection to us, I'm sure I'd pass on this in favor of something more personalized.

Eh. I figured that's what the user picture was for on the user page.

Another form of customization / personalization. As long as it didn't make the site too cluttered, I'm all for it.