UPDATE:The nuvi 750 and 760 have added new features that negate this issue somewhat.
Earlier today I posted a link to a thread on GpsPasSion, where folks are discussing the weak feature set found on the Garmin nuvi. The original poster, Mike, AKA The Office Maven, put together quite the tome, comparing the nuvi with Garmin's Mobile XT. He pulled the file due to bandwidth considerations, but I'm posting it here, at least briefly.
I thought I had a distributed solution to the bandwidth issue, but I couldn't quite get it to work. Now before you download this, you should know that it is a self-extracting compressed file in RAR format. It is 5.08 MB (5,332,975 bytes) in size, a 131 page Word document. Here's the link:
As noted in the comments below, a reader named Daniel has been kind enough to post this file on RapidShare. So if you download there, it will save me some bandwidth. Plus, it's posted there as a .doc file, in case the self-extracting zip (.exe) file above makes you nervous. Here's the link...http://rapidshare.de/files/31752451/Garmin_Mobile_XT_vs._Garmin_Nuvi.doc