The domain you choose has more ramifications than just search engine performance. The problem with strange TLDs is that:
- They can confuse visitors
- They are almost always more difficult to remember than .com, unless they spell something or sound like a word or phrase.
- They can have a tendency make your orgainzation or site appear less reputable than you actually are.
Here are some choices, and my comments:
The ubiquitous, "everything bagel", .com is the TLD you want. Assuming, of course, the one you want isn't already taken! Some of the hardest .com domains to find are "short" ones. Try to find a .com domain like "whiz". You can't. Even the .net versions are already taken!
.net / .org
Theese two other non-country specific TLDs are good second choices, if you can get one. But, they lack the familiarity of a .com, and for some sites that's unacceptable. However, for certain applications or audiences a good easy-to-remember .net or .org address can be cool.
This TLD was made popular by sites like del.icio.us. The .us TLD is great for those targeting a primarily US-based market. But unless, like del.icio.us, the full site url actually does something like spell a word, they probably have little appeal, because they simply won't ring off the tongue as "familiar".
Early adoption by spammers and other less reputable operators have tarnished the .biz and .info domains.
These are intended for individual use, but .name has never really caught on, and so it just doesn't "cut it". I could never imagine a "peterbromberg.name". Could you? Doesn't even sound like "The Internet".
There are hundreds of other country-specific and industry-specific domains available, but most lack the recognition required, so for a global site it's usually safer to stick to a generic TLD. A few country codes have gained credence in niche areas, like the Federated States of Micronesia (.fm) for music sites, Tuvalu (.tv) for TV sites, and the Tonga (.to) as in "kickme.to".
Stick to .com if you can. The .net TLD is a good second choice. If you're interested in the official list, here it is.