If there are, I can't see any. I don't have much time to go over the (very long) list of problems with the system since I have to go soon, so I'll just point to a few of the bigger ones.
It breeds a very 'us vs them' mentality. People will vote for their party simply because it's their party and without regard for who they're voting for is, as well as turning the system into merely picking who is least terrible instead of choosing who is legitimately best for the job.
It robs people of meaningful choice in deciding who gets to govern them. You know how people complained about games like Mass Effect dissolving complex issues into blue and red? Same difference, right down to the colors (at least for the US). There's a wide spectrum of choices and ideals between 'Attempt peaceful negotiation with chance of failure' and 'punch guy in face before he has a chance to ruin everything', but those sides aren't permitted to be represented in any meaningful way.
I mean, I tried Googling this. All I see are articles on how awesome a two party system is (without going into meaningful details) with anything mentioning 'disadvantages' ending up not being directly related to the system as a whole.