I recently upgraded Internet Explorer to version 5.2 for OS X. It now supports Quartz (silky smooth text) rendering at just about every font size. I turned it off though. It just doesn't look right for smaller pixel sizes -- especially when non-aliased fonts are clearer without the smoothing. I love it on larger font sizes. Just wish you could set a threshold. Maybe it's just something you get used to. 5.2 does seem a bit snappier which is nice.
Also downloaded OmniWeb today -- a promising browser, from a great Mac software company. I hear that it's cookie management is worth the $29.99 license fee.