buckworks - 9:36 pm on Jan 23, 2010 (gmt 0)

So far as we know, the .tld does not carry any inherent advantage or disadvantage. The ranking potential of a .pro site (or any other .tld) would depend entirely on what the owner did to develop and promote it.

Having a keyword in the domain name might convey a slight advantage but even so, the owner would have to do the right things with it.