I think WDW's key advantage is simply size. From my point of view, WDW = quantity, DLRP = quality.
That's my view anyway, I'd like to hear what actual WDW visitors think...
the quality aspect has been gone for about 13 years in Paris (which will be back after TS and ToT open I'm sure)....
WDW (and DLRA) gets updates pretty regularly and most of the rides have been redone to new standards at a point where DLRP just maintenanced its rides... making all of DLRP original opening rides the oldest of all, and thus the worst.... all rides are running on 15 year old technology, while there have been a lot of breakthroughs in AA and conveyence methods that have been applied overseas.
I haven't been to WDW myself, but keep myself pretty updated, and I've visited DLRA twice in two years, in which they completely redid most of the rides over there, So every ride we did overthere was different from 20 months earlier, which leavesme with the following conclusion in which rides are better or worse:
better @ DLRA and WDW:
Haunted Mansion holiday - love the theme and superbly done
Indiana Jones - This rides ROCKS!!!! a jeep trek through a temple... WOW. (Dinosaur in WDW)
Pirates of the caribbean - Sparrow Rules!!! and the new effects are amazing
Splash Mountain - Why hasn't this been built in Paris yet?

??
Soarin' - the only ride that is a more than worthy successor of a Circlevision theater...
Tough to be a bug - 3D-movie with animatronics and real involment with the audience
Muppetvision 3D - same as above, only with muppets.. they have actual pinguins as an orchestra which are IN the theater and not on screen.
Monsters Inc. - simple but great for kids (and adults to)... bring it to france please!!!
Better in DLRP:
BTM - Faster, Bigger and more original because of the Island.
Frontierland - the only one of all the resorts that has a complete storyline that covers all of the land
Star Tours - the only version that actualy is convincing enough that you on an interstellar spaceport... all the others are the same but not convincing enough to get the spaceport thing going.
Space Mountain - even with M2 this one has more to offer, while the original version from 75 and the anaheim version are pretty fun to.
La Chateau - the rest are small and too european to be impressive
POTC's location - while DLRP's version is currently technicaly the oldest around, the fortress is the most eleborate of all the versions.
Peter Pan - same as in US but with double the seats.
Main street USA - almost the same.. DLRA is charmingly small and breathes walt all the way, and WDW's look preety much the same, DLRP's version has the wonderfull arcades, which are great on busy days to provide shelter from rain of just to avoid crowds.
all the rest is pretty much the same (or I haven't experienced yet).