Literaly one of the most funny and well written reports I've ever read on Nugget Bridge.
http://nuggetbridge.com/reports/ruby-slippers-top-4-australian-nationals-report/
Ìt's basically a rhythm game. You download a song that's called beatmap from it's official site and you try to hit the marks with precision and fast reactions.
Here is what some of the most experienced osu! players do.
EDIT: That's a song in the Insane difficulty.
Never, never, never, never, never, never and NEVER use a TV for PC gaming, the input lag is horrendous on most TVs.
What resolution is your current monitor?