Another nice thing about the PS3 is that you can get a TON of storage space for your system for very little money. You can find a good deal online for a very high capacity storage device and easily upgrade the HDD on the PS3 without having to purchase a proprietary HDD like on the 360. Doing so doesn't even void your warranty, and Sony even shows you how to do it in the system documentation. (Of course, you should always go ahead and do some research before hand).
For me, I love having my PS3 available to hold DVDs I've ripped and transferred over to the HDD (I do this for the movies I own that I just wouldn't feel like digging into my DVD collection for to find the disc in order to pop it in), it's great for housing the mp3s and cds that I own, and it's a nice storage device for all the digital photos I have. I'm a big fan of watching the videogame playthroughs from places like YouTube and GameAnyone.com, and after downloading and merging the files together I can just transfer them right over to my PS3.
So for overall multimedia purposes, the PS3 is great. If you like baseball videogames, the most realistic and true-to-the-sport game out there is a PS3 exclusive. MLB The Show. The God of War series is fantastic, and all games from the series are now available on the PS3 only. (The original two, God of War and God of War II, are in the God of War HD Collection. God of War III came out on the PS3, and recently the two PSP games were put out in the God of War Origins Collection.) So you can pretty much play the entire series right there on your PS3.
If you like the Metal Gear Solid series, while it is possible to get the recently released HD Collection on the 360, MGS4 is still exclusive to the PS3. The PS3 is the only system where you can play all four MGS games. MGS2, MGS3 in the recently released collection, MGS4 in the PS3 exclusive disc, and the original MGS can be downloaded from the PSN.
Gran Turismo 5 is an incredible automotive simulator, and if you are a bit scared by the number of replies in the GT5 thread here on the forums, just take a look at what most of those posts are. They are incredibly nit-picky, Type A personality posts which just means that it's a damned good game and people have to dig to find something to whine about.