HD TVs are in demand. Although I would go for .com for HD TVs but .org is not a very bad extension for this name. Most extensions have already been taken and none seems to be developed properly. Worth high $xxx –low $x,xxx undeveloped imho.
Uh, have you seen what development is presently on hdtvs.com? I wouldn't exactly call that "competition" :D
OP, develop this as a blog/adwords and either develop good, keyword rich content yourself, or pay someone to go it. With Gs new "caffeine" infrastructure potentially giving even more weight to keyword bullseye matches in the domain, a name like this has more potential today than it did yesterday.