.biz / .us / .us.com - Relative merits?

[krx]

I am interested in several domains that are of course gone in .com, .org., and .net. Most however are available in .biz, .us, and .us.com - which I gather are for most purposes (in the U.S.) the next best thing (at least for non-niche [e.g., .tv] sites), tho please correct me if I'm wrong. I am looking at these like stocks, that is, long term investments. I'm looking at phrases, for example, that are not big now, but probably will be in 5 - 10 years. Can anyone comment on the relative merits of these extensions (or are they called tld's?)?

 

[Kate]

.us.com: not a real TLD but a private subdomain. You are at the mercy of the owners and it is not really popular
.us: IMO a worthy investment but you need a long-term horizon. It's picking up but not fast.
.biz: not all keywords will fit. Personally I am no fan of .biz. It's in direct competition with .com and stagnating somewhat.

I think it depends on whether you intend to develop or is it purely for resale. I would choose .us among the 3 but be patient.