I think we should have 100x100 avatars. We seem to be practically the only place on the intarweb that has such small avatars (besides devart). It has never looked bad when big avatars have been given out, and it's not like the forum styles are hurting for space. Besides, we might as well make the post bit longer because people's sigs take up so much space compared to the postbit (that's the stuff with your name, av, custom title, actual title, and location and post time)
We wouldn't even have to up the file size. 19 kb is plenty.
Some people complain that it wouldn't look even and pretty, well it's not even and pretty now! A lot of people use sprites for avs and those aren't 60x60. And sprites are about the only thing that looks good that small anyways.