Opera Software has posted the first beta (after a couple of preview releases) of version 9.0 of their namesake free-beer web browser for Windows, Mac, and Linux. Opera supports XML and CSS. It now claims to support XSLT, but I haven't gotten that working yet.
The Mozilla Project has released Mozilla 1.7.13
to fix "security and stability issues. This release marks the end-of-life of the 1.7.x product line."