It has a level but the presentation is different than the 7D. It works like a spirit(bubble) level and it will work in the portrait position.
Thanks for the real-life demo shot and the menu excerpt.
A related question:
The 7D has a 2-axis level (pitch & roll), but it looks like the G1x only does 1 axis (roll), right?
The Olympus E-M5 appears to have a 2-axis level:
I must say I'm more and more tempted by this Olympus marvel everyday -- heck, it has a cleaner ISO3200 than my 7D!