NOTE FOR HUNDREDS OF AMERICANS WHO FOUND THIS VIA GOOGLE: I'm talking about the British version of the show.
If the ending was that Sam never really awoke in 2007 at all (or did so only very briefly), and all that stuff in the 'present' was just a deeper stage of his coma (the clue being Nelson telling him 'if you feel, it's real' before Sam cuts his hand on a pen in the boardroom meeting, but doesn't notice), then Sam jumping off the building was just a way of getting from one bit of his coma to another. Not him in the real world trying to put himself in another coma to get back to the police in 1973 and keep his promise, which seemed a bit rubbish, and was what I thought had happened at first.
Apparently you can hear the flatlining on the radio, which means the end bit where the girl from the screen card turns off the telly signifies that Sam really is dead, The End.
The short version: Sam never left his hospital bed, and emerged from his coma only briefly, only to die when the operation to save him failed.
In conclusion: that was a Proper Ending, but the internet had to explain it to me. This isn't necessarily a bad thing, I read Turn of the Screw at university and never realised that the children died at the end, so I can be a bit of a durbrain.
I'm looking forward to the American version though, as I suspect they'll fold in the background story a bit better, rather than it just being an Seventies cop show with an occasional Spooky Phone Call. Someone suggested Noah Wyle bombing around Seventies Chicago in a Mustang with James Belushi, which sounds good to me.
UPDATE: according to the link to one of the series creators in the comments below, this is completely wrong. I don't care, my/the internet's ending is better.
IN OTHER NEWS: I'm restoring the old bits of the blog (that I deleted in a fit of pique, but saved first, because I didn't want to deny future generations MY GENIUS) which means that I can use the labels properly, but that anyone who uses a reader to keep up with this blog will think I had upped my productivity rate and gone back in time (LIKE SAM TYLERS!!!!!). But I have not.
IN OTHER OTHER NEWS: I hadn't seen Salvadore's song lyrics/diagrams before. They are great.