CAVEAT - I'm thinking of medium stacked cash game play here, effective stacks 100bb's, this does not translate directly to shortstacked play.
For those of you saying "tighter", think about this - what is he limping w? Yes, sometimes it's going to be AA, but usually it's not, and if you've played w the guy for a while, you'll prob have a sense of whether he'd do that.
Now, forget about your cards for a second. A limp from up front can be a huge range depending on the player (if you use a HUD, see how frequently he limps from EP - if he's open limping regularly in EP, he's a drooling fish begging you to take his money, be nice and accomodate him). Putting the player on a range is important - but in general (readless) you're probably looking at small/med pp's, some med and/or suited A's, and some pretty connectors/broadways/etc. If he rarely open limps in EP, you can put him on a tighter range, small/med pp's and AJs+ type hands.
How often will those hands hit a flop hard enough to play a raised pot oop postflop?
How often will everyone behind you (through BTN) fold if you raise? You need reads on those guys as well. Can you increase the chance that you'll buy the button (i.e., everyone through BTN folds) w a bigger raise?
After you answer those questions, how important are your cards and how tightly should you play here?