Visit here to find out how to download and evaluate the Release Candidate 0 versions of both. EBS is available now, SBS will be up within a few weeks - but you can sign up today and be notified when it is ready.
We also unveiled pricing for SBS 2008 and EBS 2008. We've made a lot of changes to SBS as a product, so the price has changed. In most 1-75 user cases, SBS 2008 Standard is actually less expensive than SBS 2003 Standard. SBS 2008 Premium is now a two box solution with an additional copy of Windows Server and SQL Server running on a second box, in order to provide a great application platform - a big request from partners and customers. There are a number of changes to make SBS CALs more flexible and cost-effective, too - see here for details.