IBM had RCU similar tech in their Mainframes, way back, in US Patent 4,809,168. Other OSes has used RCU similar techniques, it is an old idea:
http://en.wikipedia.org/wiki/Read-copy-update
Later, IBM created RCU for their commercial Unixes, and then donated RCU to Linux. I dont see how IBMs work is innovation from Linux? Maybe RCU was innovation from IBM, but RCU was not innovation not from Linux.
And because Solaris scales extremely well today, I dont see the need for RCU in Solaris. In 3 years from now, there will arrive a SPARC server with 16.384 threads. Solaris sees 16.384 cpus.
Thus, RCU is not innovative. It is just "good for Linux", but hardly innovative. It is not like Linux scales the crap out of every other OSes - if this was true, then every OS would have ported or copied RCU. And as we see, Linux has problems with scaling on SMP servers, so RCU can not be that good nor innovative.
So, can you provide a list of Linux tech that everybody just drools over, and wants? I do not consider an desktop as KDE as innovative. It is not something everybody ports or copies. KDE is just one desktop, among many. On the other hand, ZFS is something to drool over, everybody is copying or porting it. Or are you going to say that BTRFS is not a ZFS wannabe?