This week we had four new Cumulative Updates (CU) released from Microsoft for SQL Server. Each of these was tied to a Service Pack and version, with SQL Server 2005 getting CU15 for SP3 and CU3 for SP4 and SQL Server 2008 getting CU13 for SP1 and CU3 for SP2. There were not any releases for SQL Server 2008 R2 as that product is a month off on their CU patch cycle, and I am hoping to see a Service Pack CTP come out soon for that version.
A few years ago the Release Services blog posted a note on their service pack strategy. At that time the strategy was a predictable 8 week cycle for CUs, allowing administrators to plan and be ready for those releases and a "smaller scoped" SP strategy that should roll up the CUs and provide higher quality of the SPs. At the time, the Release Services people talked about releasing SP1 at six months after the RTM of a version and then a yearly SP after that.
I am one of the people that always tended to hold off on applying patches on my systems. Mostly because the testing cycles to examine our servers for potential breaking changes took away from other work that needed to be done. As much as I liked the predictable 8 week CU cycle, I didn't like scheduling the work to test and apply patches every other month. I was looking forward to applying yearly SPs to my systems, and only adding in CUs to address specific items.
There are a lot of people that have said they are in similar situations. They have higher SLA uptimes and the mandate that they will only apply Service Packs after a detailed test period. However there are also a number of people that advocate applying the CU patches every other month, and would easily forgo service packs as "rollups" on their systems.
Perhaps the time for Service Packs is over and a bi-monthly Cumulative Update suffices for most people. I have not heard of any quality issues over the last year with the CU patches, and I think that is because the SQL Server Release Services team is doing quality work. However the CU pages still say to "wait until the next service pack" if you are not experiencing specific issues. To me that says we still need Service Packs on a regular basis.
Steve Jones