Update - my GPS arrived last week, and I'm pretty impressed with it. The unit I finally chose (after much deliberation) is a
Garmin Nuvi 260.
This is not a review (yet), but here are some features that contributed to my decision:
Garmin has a good reputation
This model has North American mapping including Alaska, Hawaii, and Canada (although Canada street mapping is less detailed than US)
It gives you spoken directions, including the actual street names
The database includes the locations of 6 million points of interest (restaurants, hotels, etc), with phone numbers and addresses
The unit will recalculate your journey using an alternate route if you deviate from the original track it created
The screen is bright and easy to see
The touch screen user interface is simple and intuitive
The price was right (retails around $400, now on sale in stores around $350, and I got mine from an online store for about a hundred less than that)
This unit has an SD card slot and USB connector, and includes a photo viewer, world time clock, calculator, and currency/unit converter. Not big necessities for me, but I might occasionally use them. It does
not include a traffic condition receiver (which I mentioned previously is not a priority for me because I'm seldom commuting in traffic), nor an MP3 player, a bluetooth handsfree speaker for your phone, or an attachment that cooks breakfast. I can probably live without any of the above.
Thank you to those who provided advice. Feel free to continue contributing to this thread if you wish.