As of yesterday Apple seeds the latest Snow Leopard Beta to developers. According to AppleInsider it includes some bugfixes
- bug fixes in QuickTime X Player
- bug fixes in Rosetta
- bug fixes in Migration Assistant
- bug fixes in Disk Utility
The Snow Leopard Server beta is also seeded to devs and there are some notable new features in it:
- update to Podcast Producer
- new junk mail filter for Mail Server
- new account creation in Calendar Server
- new certificate management