If you are looking for something fun to play (be it alone or with others) and looking for a nice break from DCUO, Diablo 3 is a good buy.
If you liked Diablo2.... you will like Diablo 3. Although I have been playing with friends which usually makes games more fun.
It's original Diablo with just better graphics, the game hasn't really evolved that much in terms of gameplay. Download the demo and try it out before you buy is the best advice.
I loved Diablo 2 and waited over 10 years for Diablo 3 only to be disappointed. Try this instead http://www.pathofexile.com/
On console, it's great. On PC though, I haven't tried it myself but I have heard many bad things that were fixed in the console version.
I'm playing this game right now and so far I'm enjoying it a lot. It's a great break from DCUO which I'm finding boring and stressful at the moment. If you're not sure yet try the demo. But if you're ready to jump into this game, it also has some nice free DLC items for the PS3 version.
Thanks everyone for the input. Gonna download the demo like a few suggested and take it from there. Thank you again.