Okay, so the guessing is still going wild on the forums.

Score card:

1. A new Dr is in the offing. Punters are taking bets as to who the new guy's gonna' be.

2. Tennant will change into the: Master, Donna Noble and the hand will grow a third Doctor (the three-fold man theory)

3. Donna Noble stops Tennant from regenerating by lending him a "hand." (hint-hint, wink and a nudge, ya'know what I mean?)

4. He regenerates, but then next year he's still around, but only in flashback episodes, starting with the cybermen at Christmas, supposedly.

5. He becomes Justin Lee Collins and Rose, because she came into contact with the votex before, also gets shot by a dalek, and she regenerates into Alan Carr.

6. The Doctor, just before he changes completely, exclaims, "I'm too sexy to regenerate," and he changes back to his old self--only with a neater haircut, a trimmer bottom and less back hair.

Okay, I just made those last two up.

People are also speculating on which companion is going to get the chop.

Bets are highest on Martha, more or less tied with Rose, with Donna coming in a close second, followed by Captain Jack and Sarah Jane. Those last two are least favoured, because they have their own series--and let's face it, killing off a longtime and very beloved companion like Sarah Jane would really, really tick off us older fans so that's doubtful--although lately the BBC hasn't exactly been in the news for being intelligent and thoughtful.