Probably a new motherboard actually.
Spent the morning in in Milton Keynes, visiting the apple store. Seems like the video output from the macbook has deteriorated, and it refuses to detect anything at all through the mini displayport. It recognised the presence of the adaptor, but would not connect to either my monitor (lugged all the way in with me) or the store monitor.
Although this model uses a true separate graphics chipset, it's all built on the MOBO, meaning that a complete replacement MOBO will be required. We also checked for updates while I was there, and having updated, now the dock stutters slightly on the way up - or maybe that's just another symptom.
Now I've brought it home again because I need to back up the HDD (another thing I've had to buy: an external drive) before it goes away. And it'll be 5 to 7 working days for repair - longer than that if I have applecare organise shipping etc.
Sure the guys in the store were knowledgeable and friendly, but this doesn't make up for kit of dodgy quality (don't believe me, go read the new macbook area of the forums). I like the Macbook and the way it works, mostly, but this is the experience I'd have expected if I'd bought a budget Dell or Acer rather than an Apple. And we didn't even have time to get started on why the mail app is broken and how to fix it.
Tapestry, life and rich. I'm learning, hopefully while not being suckered too hard at the same time.