I swear to you by everything that is holy I - and my wife - have never seen the movie Splash and did not have that in mind when we named our daughter Madison. We liked the sound of the name (I think it sounds strong) and there were not that many girls named Madison 6-1/2 years ago (that we knew). Little did we know it was going to be such a popular name.
And I still don't think it is pretentious. Fer Christ's sake, it's nothing like some of the ones we've read on this thread.....