Like it or not, T-Mobile has now officially turned its myTouch brand into an entire franchise, thanks to the addition of a second model and an entire line of styled accessories — but it’s not just about the hardware. Far from it, in fact: with the myTouch 3G Slide, the carrier has actually built a custom skin on top of HTC’s Sense for Android 2.1, and all kidding aside, this phone represents one of the deepest carrier-customized experiences we’ve ever seen. Seeing how this phone arguably represents the true successor to the G1 — T-Mobile’s (and the world’s) first retail Android device — it’s pretty important that they get this right, particularly considering how critical it is for a carrier’s bottom line to capitalize on the meaty, profitable midrange of its smartphone lineup. Does the myTouch 3G Slide live up to the G1′s good name? Read on.

Like it or not, T-Mobile has now officially turned its myTouch brand into an entire franchise, thanks to the addition of a second model and an entire line of styled accessories — but it’s not just about the hardware. F