Missed that :O

http://paste.pocoo.org/raw/415260/

So this is the little "Shield" icon if the unit is marked as maintank.

List of stuff I noticed:

1. You lack the namespace header (which is used in every other file in oUF/element).
2. Missing ability to override the Update function. Check other elements.
3. Create a git format-diff if you can, but not required. One for API-6 and one for master if you can be arsed.
4. Fix your indenting. It's currently inconsistent.
5. Don't use select(), just use _ for the un-used locals.
6. Change MaintTank to MainTank.
7. Review your code to spot anything I didn't spot.

I'll do it myself if you haven't within 24 hours btw. >:3

http://paste.pocoo.org/raw/415439/

Now ok?^^

Almost, I'll push it shortly and fix a minor issue with it. :)

Solved with 7bcf986.