Yeah, they are like ARM now.
They used to make their own hardware though. (KyroII FTW!!)
I believe I agree with the Most Awesome Dude, I find it very likely that it's just a very slow process getting it all done.
And Imagination are very small, I doubt they have the resources to throw at it like AMD/ATI does.
Oh and, "it's not like there will be any other serious customers for that kind of shitty GPU's, ever".
Imagination are VERY like ARM in that they design embedded GPUs that are very VERY low voltage and you probably already own several in your various mobile phones, PDAs, handheld consoles, etc. They may not make it and sell it to you but their global volumes have to be pretty big these days.
Finally: I'm with the Just Works camp for now. I'll have it working first, open source eventually. Because eventually it will all be open source.