The leaked version worked fine, no problem, but I just noticed in either my WindowsUpdate.log or CBS.log it was still showing a reference to the KB.
I might be misreading what I was seeing, but this is information only, not really a problem. Since I have done a image restore back before the leaked version and since done the normal update, my logs will no longer contain the info so I cannot check.
My first experience with Windows 7 SP1 (Beta) was when I was still a TechNet Pro subscriber (probably will purchase the Desktop subscription if I like Windows 8 Consumer Preview). It ran well on my HP desktop, however the uninstall was a total mess. Fortunately, I was running an evaluation version of 7, no damage done.
Post SP1, mixed issues. It runs perfectly fine on my desktop. But on my notebook, a MSI FX603, SP1 caused an issue that couldn't be resolved through the available hotfixes (at that time). What happens, is that I can see my backup drives fine while doing a backup. But when I attempted to recover, the notebook couldn't "see" any drive to retreive my backups from. I tried all of my backup drives, even the USB 2.0 (I have 1 USB 2.0 & 2 USB 3.0 ports) couldn't see the drives. Like I said, I tried all of the solutions that I could find at the time. Even the Microsoft Answers forum had no additional solution to offer me. I even checked for updated drivers, mine was current. There was a beta one, but I passed on that. While I do try many Beta software offerings, drivers aren't one of them.
So, I uninstalled SP1, and guess what? My notebook could see the backup drives, and recover. I'll wait until SP2 is released before installing a SP on the MSI. It's running perfectly fine as is, so SP1 really offers me nothing. But as I stated, it did make a few improvements on my HP desktop. Boots faster (knocked almost a minute of time off, from pressing the power button until having a usable desktop), power consumption is down, runs cooler.
I suppose that it depends upon the computer that it's installed on. But for most, as I've noticed, many users have benefitted from Windows 7 SP1. Hopefully SP2 will arrive within a year or so, probably will be 2 years after SP1, as with many recent SP's.