How do I determine the level and XP reward of mobs in Diablo III?

I'm a little lost on this one - how can I determine what level the mobs are that I'm fighting, and additionally, how can I see the XP reward from killing in each one?

I MIGHT be able to determine this by watching the XP bar grow, but that's not very useful or easy. And I still cannot determine the level.

I don't know of any way to access this. I did a quick search hoping that there'd be results on some type of combat log (similar to WOW, which shows stats on damage, status change, and XP) But from my search, I didn't see anything come up. A combat log may be a feature we see in the future.

There is no way of determining a monster's level as of now. If you want to know the XP from killing a monster, you'll have to kill one, and then see the difference in experience points. This value will change when you level up, however.

Monster level can be determined by searching offline databases for the monsters name you are interested in. When using d3db.com, I highly recommend the Firefox "Firebug" plug in for searching of the link text, since the names tend to be non-sensical (but the link text makes sense).

Do note that monster level depends on difficulty level, so you'll see 4 levels listed for each monster (corresponding to the 4 difficulty levels).