A SSD is awesome. The boot time (if you care about that) gets down to about 20 seconds from pressing the power button to fully loaded desktop. Applications start up almost instantly, loading and saving is faster, installing downloaded software and copying large files is significantly faster. Running out of memory is not an issue anymore, since swapping to the SSD is much faster and doesn't slow down the system.
That's about it. The downside is the price, so right now I'm stuck with 128 GB, which is enough, but makes me think twice before installing stuff, and I keep music and pictures stored online now.
I don't have first hand experience with hybrids. The idea seems to be to have a small SSD cache, a large HDD, and an intelligent controller that recognizes files and applications that are accessed frequently, and stores them on the SSD, to speed up their use. I don't know how useful this is in practice, probably depends on how the computer is used.