I read a review earlier that stated the Garmin 760 displays the current speed limit of whatever road you are currently on in your travel. Very cool feature, although a minor one that certainly wouldn't push me one direction or the other. Like a couple of you, I too am considering a TT 920 or Garmin 760. I have done a lot of reading of reviews and what it comes down to for me is that I really like the feature set of the TomTom 920, however, I'm concerned about the routing. I currently have a Garmin c340 and have been fairly happy with it.
However, its routes aren't always spot on and I certainly don't want anything that is worse. Features are nice (like what the TomTom 920 has), however, if the routing is mediocre and mapping isn't as accurate as what I currently have then the features don't mean much.
Just my 2 cents as I'm trying to figure out what direction to take. I'm actually now considering just holding onto my Garmin c340 for 6-12 more months and just wait to see what else comes out on the market since I'm really in no hurry to buy.