Paddy, you're confusing yourself. There's different accelerations going on that do different things.
There's graphics hardware acceleration, which is used by games. It's the OpenGLES drivers that allow 3D rendering to be fast (and 2D, if you use it right). We have this, it isn't perfect yet though, apparently, but that's not any problem you should be noticing.
The hardware acceleration being added to VLC is usage of the DSP for decoding. It's not accelerating the drawing of the graphics in any way, just taking the encoded frames of the video and making a raw frame that can be drawn to the screen.
The window manager isn't being accelerated by either of these. It's just raw video drawing. There aren't any "drivers" so to speak, because there doesn't need to be. You need drivers on a PC because every graphics card is different, and the drivers help make things uniform and easy for the OS. On the OMAP, you want to draw something to the screen, you just draw it to the framebuffer, no need for intermediary drivers.
On that note, if things are slow, it shouldn't be because of the graphics or anything. If it's slow, it should genuinely mean that it is just slow, and hardware accelerating the window drawing won't make a difference. I don't know why you would say it's slow though. I don't have mine yet, so I can't see what it's like right now, but when I played with skeezix's prototype, it was pretty smooth.
