The parser currently allows us to reference expressions with the DELETED prefix in an OUTPUT clause. This should not be allowed: it causes wrong results, or an unhandled exception in the optimizer - which terminates the connection.
Two examples in the Details section below. There are any number of 'fun' ways to break things using this flaw. Raised against CTP 3 because the problem is not fixed there - it applies to all current version of SQL Server as far as I can tell.
For more information see: