The i3 / i5 igp's are actually quite good for blu-ray playback. I have been eyeing them for a potential HTPC for a good while now, and with them, the cpu utilization is extremely low. Couple that with being able to output lossless HD-audio formats, and it's quite a great little board.
For gaming, this will not be enough GPU power. For htpc, which it was made for -- or even for a htpc / render station combo (which I'm looking into one for), this might be a perfect solution. The only thing I don't like is only having one pci-e port...but if you need more, then that's not what the mini-itx build is for; not a fault of its own, just not what you need.
As far as raid, well...there are esata solutions for that.