I made the habanero mead that's in the recipe section of this site(
http://www.homebrewtalk.com/f80/habanero-capsicumel-60272/), and I have noticed that it seems to have gotten hotter with time. A few months after making it, it wasn't that spicy, a year later it left a nice burning after tasted in my mouth. I followed that recipe exactly except that I used 2 habanero's instead of 1. However, this recipe uses a ton of honey(I only did a 1 gal batch), and it's like a spicy dessert wine, and very thick, if I do this again I would definitely cut back on the honey.
I'd say just take a traditional mead and toss some habanero's in the primary and see what you get. 1 or 2 hab's per gallon would probably be safe.