This is a good news from the Microsoft about SQL Server Release Services for both versions SQL Server 2008 & 2005.
SQL Server 2005 SP4 can be released in Q4/2010 and the support will extanded & will be available through 2016/04/12 (ymd). For more specifics you can check http://support.microsoft.com/lifecycle/
SQL Server 2008 SP2 - targets release in Q3/2010!
More info about this announcement, check here