I'll say what I think about few types of music that I listen the most;
- Dubstep is easiest to synchronize kills with, but there are very few good songs, and community/gamers are fed up with ridiculously large amount of montages with dubstep soundtrack.
- DnB (drum&bass) is fast and pumped up, but maybe too fast for montages except for some berserk moments in game.
- Hip-hop; it's cool if it's some saturated beat that doesn't sound shallow and empty, but rap over beat just doesn't go well with gameplay footage because it distracts the viewer. So probably something more like glitch-hop with less vocals in it.
There are many other genres and subgenres that could sound good as a soundtrack for game montage, but I've focused on these 3.
It doesn't even have to be some mainstream music, it can be some good cinematic soundtrack.
It would be nice to see what community likes to hear in montages, fragmovies, teamtages, etc...
Feel free to discuss.
I'd like to hear some DnB, liquidfunk or neurofunk to be exact, some psychedelic madness ambient lol...
Some of games I've played and enjoyed a lot, that had really good scores, were using mostly DnB and it fit perfectly with sci-fi action.