You will get all kinds of reactions and some like me still use both. Try them both out and figure out what you like and don't like. Some like that BBmaps can do north up and track up whereas google cannot. Google has more add-ons and possibly more views. Neither does spoken turn-by-turn which with more hands-free driving laws is almost mandatory.
Use both. But I wish there was more integration. For example on the iPhone, calendar entries with addresses in the Notes field can be clicked and displayed in Google Maps. Same with addresses in contacts, emails, browser.
I first switched to GMaps because it just looked better to me. After that I rarely have used BBMaps because I usually remove it, so forgive me if these features I like from GMaps are also available on it:
Satellite View: Some guys were going camping and were trying to explain to another how to get there. We were able to follow the dirt roads on the sat view, star it and send to him. (He still managed to get lost, but that wasn't a BB issue)
Street View: How cool is that on a handheld? Nice when you are looking for a restaurant or hotel on the fly and can get a look ahead of time. Freaks people out that aren't familiar with it to show them the front door of their house...
Voice Enabled Search: On the new version, you can hold down the Green send key and just say your search. I use it for finding breweries to eat at when traveling. You can even say an intersection, all kinds of things. When you select a business from the search results, it will give you options to Call them, get directions, street view, etc
Traffic Info Layer: Probably one of the features I love the most. It will also use the traffic info in its estimate of travel time on directions. Using My Location as a starting point, you can easily get directions and keep updating to check the estimate. Lots of other Layers available too.
Transport options: Directions are available for Car, walking or transit.
Probably one of the first 3 things I load on any new BB and its used daily.
BB Maps performs 10 times better. The Google maps is kinda slow updating on my Bold 9650. Sometimes I've already passed a street by the time it updates.
The updated GMaps is pretty fast.
I also like the street view, its nice to be able to actually see where I'm going if I've never been there before.
I think that and the ability to map something on my desktop and then pull it up on my blackberry later makes it way more useful than BBmaps.
Posted from my CrackBerry at wapforums.crackberry.com