Exchange 2010 SP1 RU4 Removed from Download Center – Jo?o Ribeiro – Site Home – TechNet Blogs:

We have discovered an issue impacting some customers who have installed Exchange 2010 SP1 RU4 into their Exchange environment and as a result have removed SP1 RU4 from Download Center. We recommend customers do not proceed with any planned deployments of SP1 RU4.

Anyone see a trend? First RU3 now this. Suggest customers stay on N-1 for the forseeable future.