I like the look of some bullpups. Not many though.

The thing I see as the big advantage is you get a maximum barrel length for a minimum overall length by pushing the barrel back into the stock. I see that as a big advantage in urban/close-quarters fighting. No long weapon to attempt to swing around in a narrow hallway.

I think compact is easier to carry--even when not in use. A standard rifle you really have to make a choice between carrying it in a way that it doesn't swing much (like slung diagonal across your shoulder) or carrying it in a way that is easy to quickly shoulder and use.

That's my 2¢.