Network World did a great summary of the announcements yesterday

Microsoft released Essential Business Server (EBS) 2008
Windows Small Business Server (SBS) 2008

Key points:

1) The WESS offerings bundle popular IT software in order to ease rollout and management burdens for small and midsized companies
2) The two bundles represent Microsoft's best attempt to date to serve the needs of businesses that have up to 300 PCs.
3) WESS offers small businesses for the first-time options to deploy multiple servers, mobile options, a platform for small companies to run business applications and the first integration between small business infrastructure
4) Microsoft's online services as part of its software-plus-services model.