It does have that reputation. The learning curve is extremely steep. But once you go over it, DOTA 2 just sucks you in man. Very VERY addictive.
I myself didn't found it that hard getting into though, maybe because I played tons of RTS games when I was young.
But now when I look at it, it is indeed full of STUFF to get used to. I mean if I have to explain it to a newbie, it takes forever.
Best thing to do would be to watch some introductory videos on YouTube, they could help a lot.
P.S That item is called Shadow Blade. The gunman must be "Sniper". He is a Abuses will lead to ban, gets really powerful mid-late game.