Snow Leopard was released Friday and is getting nearly 100% good reviews. There are very few tweaks to the user interface, but major streamlining "under the hood". It actually has a SMALLER footprint on your HD - opening up 6 - 10 GB of disk space over Leopard. All reviews say it will make your machine considerably faster in most tasks. $29 to upgrade - and you can jump right from Tiger to Snow Leopard if you never used Leopard. It will only work on Intel machines though - keep this in mind if running an older Mac.

I pre-ordered from Amazon, but my copy will not ship until 9/1. I will post my thoughts after getting it and running it for awhile.