I just bought myself a Gameboy Advance SP and a TV-tuner to go along
with it as I wanted some sort of way of watching TV and being able to
record it (with my camcorder) while travelling as I am right now.

It seems to work very well! Even has the ability to handle all the
different PAL systems.

I have one question though, which the manual doesn't seem to cover: a
game cartridge HAS TO be inserted into the tuner (don't ask me why)
-any game cartridge, but how do you choose to play games as opposed to
using the GBA SP for watching TV?

It's a bit cumbersome to have to unplug the TV-tuner, remove the
cartridge, then re-insert the cartridge into the GBA SP every time I
feel like playing a game.....

Hallvard