The Watcher was never really explained properly in the story, but the BBC website describes him as "a wraith-like intermediate stage between the Doctor's fourth and fifth incarnations".
I've not seen ToaTL (nice acronym!), but the site has this to say:
"The Valeyard...is an amalgamation of all the Doctor's evil, and is between the Doctor's 12th and final [13th] incarnation. [This distinction would only be made if the Valeyard is different from the Doctor's 12th and 13th selves. Thus, he seems to be of the same nature as Cho-Je (Planet of the Spiders) or the Watcher (Logopolis), a projection of the Doctor's future self, one which might not be like what the 13th incarnation actually turns out to be."
Back with Journey's End (http://www.bbc.co.uk/doctorwho/s4/episodes/S4_13), my latest theory is that the Doctor's regeneration somehow blasts his 11th incarnation apart from the 10th, out of the weird Dalek time pocket and back into the normal universe.
Doctor no.10 might stay in the Medusa Cascade, or he might not. I reckon this could be another Doctor-lite episode and mainly focussed on the (many!) companions.
The Christmas/next year specials could then take place with Tennant, before we catch up with Doctor no.11.
But hey, my theories on what's going to happen change on an almost daily basis at the moment :o)
Re: SPOILERS!!!!
I've not seen ToaTL (nice acronym!), but the site has this to say:
"The Valeyard...is an amalgamation of all the Doctor's evil, and is between the Doctor's 12th and final [13th] incarnation. [This distinction would only be made if the Valeyard is different from the Doctor's 12th and 13th selves. Thus, he seems to be of the same nature as Cho-Je (Planet of the Spiders) or the Watcher (Logopolis), a projection of the Doctor's future self, one which might not be like what the 13th incarnation actually turns out to be."
- Watcher (http://www.bbc.co.uk/doctorwho/classic/episodeguide/logopolis/detail.shtml)
- Valeyard (http://www.bbc.co.uk/doctorwho/classic/episodeguide/trialtimelord4/detail.shtml)
I guess that counts as canon.
Back with Journey's End (http://www.bbc.co.uk/doctorwho/s4/episodes/S4_13), my latest theory is that the Doctor's regeneration somehow blasts his 11th incarnation apart from the 10th, out of the weird Dalek time pocket and back into the normal universe.
Doctor no.10 might stay in the Medusa Cascade, or he might not. I reckon this could be another Doctor-lite episode and mainly focussed on the (many!) companions.
The Christmas/next year specials could then take place with Tennant, before we catch up with Doctor no.11.
But hey, my theories on what's going to happen change on an almost daily basis at the moment :o)