This is an important consideration. The vast majority of my 300,000 Marriott points have been earned at Residence Inns on 30+ day stays (just the nature of my busines). I'd be well over 500,000 if I spent more time at the "10 point properites". For me, especially on long stays, the extra benefits of Residence (bigger rooms, full kitchen, availability of separate bedroom rather than just studio, decent b'fast and afterwork munchies, USA Today, etc.) make it worth the points sacrifice. It also has worked out that RI's tend to be better located from my specific destinations. When you're just looking at week-to-week posting, 3,500 points doesn't seem like a lot. But I can attest to the fact that those "lost points" do seem painful once in awhile.

Does anyone know the precise reason for the difference in points? It's not like the room rates are that different. And we can, of course, speculate that it has to do with longer term stays. But Marriott should really start offering 10 points per $$ for RI - and they really ought to do it on a retroactive basis!