Ed Parsons just posted about actionable location intelligence on mobile devices, and talked about recent enhancements Google has made to its mobile service in the UK. I think Google Maps Mobile is great, but I think it's still a good bit behind the Telenav software which runs on the BlackBerry (and also the navigation system in my Toyota Prius! - I posted about both of these previously - see also my short photo-based review of both of these on flickr).
The two key features which Telenav provides which Google Maps Mobile doesn't yet are integration with the built in GPS (or any other location determination capability), and the ability to give directions which are safely usable while you're driving - i.e. a combination of spoken instructions and large turn graphics. A third feature which is helpful too is integration with contacts on the BlackBerry - the ability to type a contact's name and use their address as a destination (TeleNav has an advantage here in developing their application specifically for the BlackBerry, it is harder to do this if you're supporting a broader range of devices).
I currently have four different pieces of mapping/geospatial software on my BlackBerry 8800. Here is the very short review on them (I will try to do a longer one at some point), in order of ranking from most favorite to least favorite:
Telenav - a really outstanding piece of software, I have been extremely impressed. The user interface has been very well thought out, it fully takes advantage of the built in GPS, either to give you a map of your current location or to do real time route guidance, and it has excellent spoken directions with clear turn graphics in either 2D or 3D styles. The business finder works very well both on categories and business names, and appears to be very up to date (I tried one example of a business which had moved about three months ago and it found the correct address). Its maps are pretty nice but it has no imagery capabilities, just street maps. There is a charge of $9.99 a month for this service.
Google Maps Mobile - my previous favorite until I got Telenav. As noted above, the main things it is lacking are integration with the GPS and lack of spoken driving directions. However, the step by step directions capabilities are still very usable - especially if you have a copilot while driving, or if you are walking to your destination. But the map quality and performance are great, and it supports imagery which Telenav doesn't. The quality of the "Satellite View" images on the BlackBerry 8800 are really impressive. You can scroll around the map in all directions using the "pearl" trackball, which is another nice feature. There's also a "show traffic" option which is cool - if I'm not mistaken, this appeared on the mobile version before the standard Google Maps. It shows traffic congestion on freeways, with a green / yellow / red coloring scheme. This is a free offering.
BlackBerry Maps - I haven't used this too much, to be honest. The maps look clunky compared to both of the previous two. It has pretty basic GPS integration - you can center the map on your current location. The directions capability is rudimentary - it gives you a text-based list of turns, or an overview map, there is not a step by step turn capability as with Google and Telenav. I just found that there is a "Send Location" capability, which is a cool idea - you can send your current location to someone via email, SMS or MMS, which includes a link with your latitude and longitude and the ability to display a map. However, what is less cool is that the link only works on a BlackBerry with BlackBerry Maps installed. But this is a great idea for someone to implement in a more generic way. This is also free software.
Spot for BlackBerry - frankly I have been disappointed in this, it doesn't seem ready for prime time. It touts some interesting features, like the ability to import and export GPX files. I was interested in this for geotagging photos using RoboGeo (which just cross-references to a GPS tracklog based on time, and so records the location of all the photos you have taken). However, after quite a lot of messing around, I found that while Spot apparently records a tracklog (you can see this on the map, if you look hard), the export GPX capability doesn't export this, it only exports waypoints which you have specifically logged. It has the ability to access any WMS map server, which is interesting, but the default maps it is set up with are not nearly as nice as the other three. I found the user interface very clunky compared to the other three. With some work, this could have some good capabilities, but it's not quite there yet. This costs $49 (a one time charge with no subscription).
So I'm still looking for some software for the BlackBerry 8800 which will be able to record a GPS tracklog of where I've been (just running in the background while I'm using other capabilities), and be able to export that to my PC. I'd also like something which can report my location regularly back to a server (TeleNav has a workforce management solution which includes this capability, but it's a bit more heavyweight than I need). This may be my opportunity to brush up on my Java coding :) !