Debian has posted their 6.0 "Squeeze" release goals for the release coming at some point in the future. As always, the Debian team is focused on support for multiple architectures, speed, and stability. Of note though is full IPV6 support (hasn't that been in Linux forever?) and faster boot time.
In a related note, they also announced new time based release plans, adopting a 2 year cycle. Personally I think that 2 years is way too long, and will drive any desktop users to something like Ubuntu (which will have 4 releases in that timespan). For the server though, this isn't all that bad :)