The little thing is that the name WordPress is due to Christine Tremoulet, who blogs at Big Pink Cookie.
The big thing is that Automattic will build BBPress, which currently powers the various WordPress forums, into a product called TalkPress. I think it’s safe to assume that TalkPress, like BBPress, will be free/open source software.
I note that Matt has registered talkpress.org, but that there is no server there yet. There is a server at talkpress.com. I assume that the .org site will house the software, and the .com site will host TalkPress forums (i.e. that the .org and .com sites for TalkPress will correspond to those for WordPress).