I find this personally a bit odd, but also a neat quirk ;)

It hadn't struck me until I saw the episode where they end up in an alternate Earth, where the Doctor puts his glasses on to check out a computer.

(This is practically nonspoilers, since I am not going to reveal any details ;))

I had noticed him wear glasses occasionally since he became the 10th doctor, but... it didn't really spark until tonight.

Anyways... ;)

Go Doctor Who! :) Gimme some cat male aliens, dammit ;)