TomTom updates its GO series of navigators with a new capacitive touch screen and an updated graphic interface.

TomTom continues to update its line up of GPS navigation devices. This time, it has announced the two newest models of its top-tier GO line of GPS navigators, the TomTom GO 2405 TM and the GO 2505 TM. These models feature a new external aesthetic, an updated user interface, and the promise of faster routing.

The GO 2405 TM and GO 2505 TM differ from one another only in screen size (4.3 inches for the 2405 and 5 inches for the 2505). Both units feature glass capacitive touch screens that allow users to swipe and pinch their way around the TomTom interface. There's also a new metallic chassis with an asymmetric rear-panel design and a suction-cup mount car cradle that holds the GO unit in place with a strong magnet for easy attachment and release.

One area where TomTom has typically struggled (at least in our eyes) is its menu structure and graphic user interface (GUI). The TomTom GUI saw marked improvements with the entry-level TomTom Ease and further refinement with the XL 350 and XXL 550 software update. The new GO models feature a further evolution of TomTom's interface with dramatically improved graphics and reduced aliasing on the map screens, vibrantly colored icons in the menus, and easy-to-read text throughout. The new screen is a gem, and the updated interface really shows it off.

You probably won&39't spend much time admiring the GO&39's asymmetrical rear panel.

Beyond the eye candy, the GO series seems to benefit from TomTom's simpler home screen interface, which puts the option most often used front and center and hides lesser-used options in nested menu screens. At first touch, we like what we see, but we've already discovered a few quirks deeper in the menu structure that will merit mention when our full review goes up. For example, there are no back buttons anywhere in the menu, and so far, accidentally tapping the wrong icon means we had to jump back to the map screen and start over with whatever we were doing. Also, some menus, such as the Advanced Options, are simply long multipage lists of check boxes that users will have to wade through in their entirety just to make one change. These are only our first impressions and perhaps menu navigation will get easier as we spend more time with the new GO and learn more about the control scheme.

The TM at the end of each model number is an indicator that these units benefit from TomTom's lifetime RDS-TMC traffic service and lifetime map updates. Both units also feature text-to-speech, voice recognition, and Bluetooth hands-free calling when paired with a compatible phone, which should make you feel a bit better about the GO 2405 and 2505's MSRPs of $299 and $319, respectively.

The new TomTom GO series models are currently available only at Amazon.com, BestBuy.com, and TomTom.com in the United States and will see widespread release to brick and mortar retailers in mid-2011. We have a GO 2405 TM in hand and will be evaluating its performance and user friendliness over the next week. Stay tuned.