Tom's did a feature on the Fusion IO drive back in 2007 iirc. Doubtful we'll see a drive like that in the consumer market for years.
I always felt that SATA was almost a step backwards when PCIe has always been so much quicker. I'm kind of surprised the SSD market isn't already completely PCIe-based, considering how much more raw bandwidth it offers compared to SATA and that the big thing about SSDs is speed. I have a feeling once SSDs start going mainstream and start replacing HDDs, we'll start to see the SATA bottleneck hit more and more often, and that's when the big hardware companies will start to look into PCIe for storage.