In other words it's still a "test patch". If you don't currently have issues with your SP2 box, wait till the patch goes final. Never know, could break more than it fixes ;o
The most important change will be a supposed 10% performance boost. I hope that's not an exaggeration. Also Network Access Protection from Vista is to be included...
That's utter rubbish. The rumour was started by a site running benchmarks in a Virtual Machine. (:rolleyes There may be performance improvements, but I'm willing to bet they won't be noticeable.