It has a cool trick called "infinite analysis mode," where you can follow a game, and after each move you Fritz will think for as long as you let it trying to figure out the best next move.

You can use Fritz too.  It is not just for GMs.  If you use Fritz to train yoursef you will get stronger.  Yes it analyzes games.  You can use the function called blundercheck to see which of your moves gave the game away to your opponent ( if you lost ).  Playing directly against Fritz will not do you much good because it is so strong.  But asking its opinion about your games is a great way to learn.

Strong as a Grandmaster?!  Man so its pretty much for people that are at there level right?!  Does it anaylize games?!

Fritz is chess playing software.  It is as strong as a grandmaster.  I dont know about Macs.