This is becoming more and more common, notably on spinning rods, and I'm really liking it. Hoping to try it out for myself on my next build.
See the Phenix Feather as one example:
Here's the new Edge Delta LMX as another:
Anybody done this? If so, what reel seats have you been using to accomplish it? I'm guessing I'd need to find a reel seat that's pretty low profile, at least at the ends, then take care of the step down to the rod blank with some winding checks and/or epoxy ramps. The Edge, at least, looks like it's being done with some variation of the Alps Rapid Spin seat.