I believe most of the Enterprises are interested to deploy a software when the service packs are associated with it to fix most of the bugs from RTM release, SQL Server is no excuse for that reason.

Its an interesting campaign to see and now it is time to get a release on Service Pack (I guess SQL-ReleaseServices policy states), if you are interested to cast your vote then visit the SQL Server 2005 Service Pack 4 page on Connect site.

More the merrier!