I'm holding off relying on it - lots of issues with many Apps and general sluggish behaviour.
If you can - clone your boot drive and run a copy onto it and check how it works on your system. I had mucho updates and still not found a satisfactory way of using Quicktime Pro 7 even though it sort of works for playback.
So currently I'm running Mac OS X SL 10.6.8 when I'm working on critical stuff and testing the Lion Boot Disk with my apps when I get time to check I have it all running smooth before making the permanent switch.
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