Microsoft has released SQL Server 2008 Service Pack 2 CTP
>> SQL Server 2008 Service Pack 2 CTP
Express Edition is available here:
>> SQL Server 2008 Express Edition Service Pack 2 CTP
SQL Server 2008 SP2 CTP contains the cumulative updates up to SQL Server 2008 SP1 cumulative update package 8, and fixes to issues that have been reported through our customer feedback platforms. These include supportability enhancements and issues that have been reported through Windows Error Reporting.
>> SQL Server 2008 Service Pack 2 CTP
Express Edition is available here:
>> SQL Server 2008 Express Edition Service Pack 2 CTP