The first thing I would say about myself is that I have an unsuppressible passion for travel. If I were to wager what my friends would say the most notable thing about me was it would be that I seem to check-in to a lot of airports in a lot of foreign cities.
The second thing I would say about myself - to continue the airport theme - is that I have a genuine love for flying (some may say an unnatural amount love) and possess a scary amount of knowledge of all things aviation-related. (For those of similar ilk, I would choose an A380 over a 747 and Oneworld over Star Alliance and SkyTeam any day.)
In a similar geeky vein, I am currently teaching myself to code and have a voracious appetite for any tech-related news, happenings, trends, etc. Given that I was a government and history major and now a law student, these passions may seem out of place - my equally as strong appetite for US politics compensates however.
To follow the AirBnB suggestion of talking about things I like: my top 3 favourite cities are Washington, DC, San Francisco and London (with NY a exceptionally close 4th); 5 things I could not live without include my iPhone, Internet, my frequent flyer card, my credit card (I spend too much money), and my job (to pay for the preceding 4 things); and my favourite TV show is The West Wing.
On a more serious note, when staying in other people's homes I endeavour to - not to sound cliche - treat it as if it were my own, which is to say that I am neat and tidy (one look at my closet and you would probably agree), respectful and always self-aware.