Planning on buying a SATAIII/USB3 mobo - is it really worth it?

Hi, I'm going to build a new computer by the first week of october and I need some help with choosing the motherboard.
I'm always moving LAAARGE files, and since I like speed I was interested in buying one of those with sata3/usb3, but I'm quite confused now after what I read in various articles/sites/forums about the bandwith limitations of the new mobos with these new features.
My plan was a build with an i7 950, a GTX 460 (and it's quite possible that I'm going to SLI a second 460 in the next 3-4 months, would be great in pcie x16/x16), 2x WD 640gb sata3 caviar blacks (in raid 1), 2x WD 1tb sata3 caviar blacks and a Crucial RealSSD sata3 64gb.
My priorities are gaming (but not hardcore gaming) and multitasking. Not interested in overclocking.

I can somewhat understand this stuff, but I'm no expert. The only options that I have in mind are:
1) getting a motherboard with these new features like I have been planning, but they have only 2 sata3, some of them (if not all, I didn't understand very well) have bandwith problems with these new features, and even if they work correctly I'll need to expand my sata3 connections anyway if I don't want to bottleneck all of my 5 drives.
2) getting a good mobo with usb/sataII and adding in the future a load of sata3 ports in one way or another (I repeat, I'm no expert, I don't even know if this is possible!)
3) getting a decent mobo with usb/sataII and then change it as soon as the REAL gems come out within my price range.

So, what would you suggest me to do? Do you maybe have in mind some great boards that fit my needs? Let's say maximum price 200-230€ (I can maybe afford a little bit more, but only if it's really, REALLY worth it.).
Thank you for your time.