They are VERY different experiences, but there are truly exceptional moments in each. One thing I love about DL is being able to walk out of my room (if you stay and Disneyland Hotel or Grand Californian) and being RIGHT THERE in Downtown Disney. It is definitely a shorter trip - I'd be hard pressed to spend more than 3 days, or at the most 4. I'll still pick WDW as my first preference, but I certainly wouldn't turn down another short jaunt to DL. I TOTALLY beleive all true Disney-o-philes need to at least try it once :-)