loved oxford's app - and not just cuz i got in. the 2 essay format, with 2,000 words for the 2nd essay and a very open ended question is pretty awesome. it basically means you can't recycle other essays and have to actually sit down and think about the big picture of your application...there's really nowhere to hide in an essay like this and it gives the adcoms a much better chance to get to know you more as a person beyond your profile (i.e. gmat/gpa/resume).
i really wished the other schools' apps could've been more comprehensive like this.
overall, really hated wharton's app. the essay questions were interesting and engaging, and definitely focused on understanding the applicant as a person, rather than another profile. however, there were just too many essays. between the regular app, the lauder app, and the scholarship essays, i wrote something like 9 essays for this one application...what a nightmare. also i wasn't very fond of the insead application either, mainly because it's just prehistoric since you have to do it in acrobat and the formatting was atrocious. also it was extremely career/work experience centered, which was good for my background, but not necessarily good for others.