It's legal, but it sort of leaves me sour. My group didn't realize quite what an impact the Charge rule would make... for a while, I misinterpreted it as a simple +1 to basic attacks as long as you had moved in a straight line, to the closest square, etc. etc. When we found out the correct ruling, it changed our game significantly.
It helps the monsters/NPCs the most. Since monsters use Basic Attacks so often, they can Move + Charge halfway across the map to reach the PCs, even if they are trying to stay away. The monsters usually don't charge through opportunity attacks, but on occasion it's caused some trouble with the back-line strikers.
It also doesn't make a lot of sense to me. Ordinarily, a double-move means you can't attack. It seems odd that you CAN attack with a charge, even though you're not in a "Run" state. Somehow the act of declaring a charge means that you can throw a basic attack on top of a double-move. If it were a bull-rush ONLY, that might make more sense to me, but it's still a little weird that you can combine a Move with a Standard action, even if the Standard action is limited. Especially since, as far as I know, it's the only action in the game that "doubles up" like that.
The good(?) news is that the Charge rule makes it more difficult to retreat. Before the Charge rule came up, monsters who were getting crushed would double-move away, and the PCs could only hope to fling a Ranged attack or two at them as they went. Now, the front-line guys can Move + Charge, and lock up the enemies with a chance to deal some damage (and possibly an attack of opportunity as well).
I don't know. Normally, Melee Basic attacks (not at the end of a charge) are still Standard actions, which suggests that they still require the kind of time that Standard Actions require. Slapping a free attack on at the end of a Move seems to break my sense of how long the various actions take.
I don't know, it's hard to say precisely what bothers me about it. As I mentioned at the beginning, it just leaves me sour.