By Kevin C. Tofel, GigaOMAn updated Samsung Galaxy S class device called the Vibrant Plus looks to be the first handset capable of fully utilizing T-Mobile’s 4G network. The operator spent much of 2010 upgrading its 3G data network for use with 21 Mbps devices, but only offers USB data sticks with radios that can us the maximum network speeds. T-Mobile didn’t introduce new 4G handsets at CES last week, instead focusing on news of its next upgrades which will again double speeds, offering performance comparable to Verizon’s current LTE service. News of the new Vibrant Plus came in the form of leaked documents found by the T-Mo News blog, showing some slight variation from the existing Samsung Vibrant, which launched in the third quarter last year. If the leaked information is correct, the Vibrant Plus adds a front-facing video camera, Android 2.2 out of the box and will be “the fastest device on T-Mobile’s network” with full support for the 21 Mbps network. Such speeds are theoretical, however, so I’d expect peak downloads to be near 10 Mbps, which is what I saw when testing the 21 Mbps webConnect Rocket on the network last year. While it’s great that T-Mobile is set to launch handsets that can use its zippy new network, I’m still wondering if in the long run it’s alienating some of its current customers by refreshing phones so quickly to keep pace with the aggressive network improvements. The current Samsung Vibrant, for example offers all the same features, save the camera and faster radio, so folks that purchased a Vibrant on contract can’t be feeling too good about this. Even worse: the Vibrant is still stuck on Android 2.1 after on-again, off-again news of upgrades to Android 2.2. Yet the new Vibrant Plus, which isn’t that different from a hardware perspective will ship with Android 2.2. Ultimately, more powerful handsets that handle faster network speeds are always around the corner. So there’s a valid argument that revised handsets are simply inevitable and that this is just the way of the smartphone world. Indeed, T-Mobile is doubling network speeds to 42 Mbps this year and said that it would have handsets for the faster network in the second half of 2011. That may be of some small comfort to current Vibrant owners who can likely leapfrog the Vibrant Plus in another six to 12 months for an even faster phone with a more current version of Android.