Hotel vs. Merch. My thoughts...
Merch is more "expensive" than hotel nights. For example - 3 nights ($200/nt) at the Ren in Chicago is 50,000 pts - or a $600 value.
A big screen TV for 400,000 pts is equal to (5400$) in hotel nights - and that TV costs about $2000 in the store. So in otherwords - you can get a $2000 TV or $5400 worth of hotel rooms for the same 400,000 pts.
However, it might be best for you to use merchandise if you aren't finding use for the points in travel. Or (like me) you travel for work a lot - and staying in a hotel on vacation isn't #1 on your list.
THis past winter - my wife and I opted for a 360,000 Big Screen HDTV for my points. With a new baby and a long winter in MN - that was what I wanted to spend my points on. It was the right decision for us.
My theory is to spend the points on hotels if you have travel needs. But more than 100,000 pts for hotels - or no real hotel plans in the next 6-12 mo - go for some stuff. Esp if you are earning points at a pretty high rate.
Good luck.