Hi 11thDoc,
: So they didn't do a new series in 2009 because Tennant was
: going to do Shakespeare, right?
No, it was the other way around: Tennant decided to do Hamlet once he knew that Series Five had been delayed to 2010. It only looked like it was Tennant who caused the delay because the Shakespeare season was publicised before the BBC had announced their plans for Doctor Who.
: Then before he even starts Shakespeare he announces he
: will leave Doctor Who.
Tennant was already performing in Hamlet when he made his announcement about leaving Doctor Who.
: So, thanks to him not making his mind up a little quicker
: there is no series in 2009 for the fans and a few hundred
: people didn't have fulltime jobs for the year.
The reason because there is no series in 2009 is because the production team needed to take a year off after having worked fairly solidly on Doctor Who from 2004 to 2008. This had apparently been the plan for some time, and it has been indicated that one year off in every five may become an established pattern if Doctor Who continues long term.
The production break has the advantage of giving including new incoming producers Piers Wenger and Steven Moffat the vital time they need to get Series Five prepared for production.
: ... Then ironically he injures himself and doesn't even DO
: the Shakespeare, but that of course isn't the point ...
Tennant apparently needed to have surgery for an existing back problem that had flared up as a result of doing Hamlet.
: Doesn't the whole thing seem a little pointless? Why
: didn't Tennant make up his mind a few months earlier?
: Then we could have had a new series with a new Doctor in
: 2009.
If Tennant had made up his mind earlier (and perhaps he did, but it was kept secret...?), for the reasons stated above it is unlikely that it would have made any difference to the decision to take a year off.
Hope that helps to clarify things.
Cheers
Paul
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Paul Scoones