Pokerroom is available both as a no-download version and a download version. The site also lets Mac users play without installing any additional software.
Pokerroom is by many considered to have the best designed software. It comes both as a Java applet and as the standard Windows download. The Java version is especially popular among Mac and Linux users as they don't need a Windows emulator to participate in the games. As for the poker, Pokerroom offers two daily $1,000 free rolls that draw a lot of traffic. The site focuses on Texas Hold'em but has added Omaha and Seven-Card Stud to its lineup.
Thanks to good positioning in search engines Pokerroom offers there are quite a few soft games available. Many of the Hold'em games have a view the flop percentage in the 50s and 60s.
It's worth noting that Pokerroom is giving away a WSOP seat worth $13,500 in June 2005.