I think tinyurl is a good domain as it says what it does. Im not sure if it would work with something very short for example ab.us as people are not that lazy and l also think trust plays a part too.
tinyurl is a very unique ideal name
Guessing it takes a lot of work and $$$$ for surfers to pick up on a new url shorting service.
I have the software and think 1000,s do and short domains but its a market thats not as easy as it looks to succeed in on a big scale.
Just my
