Macbook Pro (Early 2011) running hot with OS X Lion
Because you have a base unit, your machine has an integrated GPU. So just looking at CPU cycles can be a red herring.

You can test this behaviour by turning on Cover Flow in iTunes and scrolling through your entire library for a minute or two. Since it is quite GPU intensive, after some time, your fans will ramp up to bring your chips temperature down. Bt if you consult your CPU usage, it will be quite minimal.

It could be the case (very likely) that Lion is working as intended. Lion introduced much more animations and graphically intensive processes, such as swipe animations when navigating websites using the trackpad, pop-up animations on dialogue boxes, swipe animations when sending mail, etc. Even moving or re-organizing icons in Finder now has an animation attached to it

You are certainly free to take into an Apple Store and talk to a Genius about your concerns, but I'm fairly certain they will test the unit and report that it is very much within "spec."