The lumps you see in the picture were once dark chocolate pieces from one of the top chocolate brands, and had an expiration date of May 2012. They were stored in the pantry all this time and forgotten...
Tastes fine to me today (no rancid smell/taste, etc) but I'm wondering if they're still ok?
Sent by Nisha
Editor: It looks to me like your chocolate melted at some point (or points!) and re-solidified, which accounts for the dusty "bloom" you see on the surface. It's still safe to use, but probably doesn't taste quite as good as when you bought it. I'd use it in something where you melt the chocolate down, like brownies. Here's some more info on chocolate bloom:
Readers, what do you say?
Related: Handy Tip: How to Melt Chocolate