Amen to all of your comments. As for "how hard is it to fix?," if the problem vis-a-vis Travelocity et. al. is that they're running and programming the site in-house, they're in serious trouble. There are plenty of professional operations that would give them all of the access to programmers they need. A quick measure of Starwood's management is whether they've outsourced the web operation.
That said, the web site is very poorly designed, for exactly the reasons given above. Management should consider that users aren't on T1 lines (too much superfluous stuff on each page, too many pop-ups) and they we sometimes like to check out more than one property in a city. If the programmers tell them that it's very difficult to fix this, get better programmers.
Do I sound like someone fed up with prima donna programmers?
P.S. A couple of weeks ago I found a better rate for the SFO Gateway Sheraton on Expedia. Since SPG doesn't give us anything for online booking, I booked it. I forgot to give my SPG number, but the hotel had it when I checked in. I don't know who to thank, but good job.