When buyin a domain, what exactly do you look for?

[RyanLanane]

Also, can someone explain when they say "That is ranked as #2 in overture" etc. etc. etc - In other words when people are buying domains and all the things they look at can you guys please elaborate exactly what defines a valuable domain name.

For example, if I am looking at a comparison of the things that are important betwen porno.com and porn.com could you should me what the results are for each site and how you get these?

I know this is a hassle, but I am interested in learning more about this - Not that I have many domains worth much more, purely for the sale of learning