It’s not true: it’s not only .com domains that have resell value. I see .info TLDs (Top Level Domains) selling like hotcakes. Some registrars have a sale on them, and people are buying them up on one year’s registration and reselling for a small profit.
Some people are even building a static website using a cheap multi-site hosting account, adding about 10-20 pages of content having Google AdSense ads, and then selling them for $150-$200 at Sitepoint Marketplace, or one of the numerous other places. Not a bad return for a bit of work and low startup costs. (Hint: hobby and health topics seem to sell the most.) My observation is that .net and .info TLDs seem to be popular for this activity.
The .tv TLD is an area that I think will become hot. (Is that hard to see; not exactly prophetic, since Internet TV is growing huge.) Because the yearly registration costs range from $25-$39.99, there are still tons of great choices. Actually, the reason for the availability is due to a historic problem. The .tv TLD stands for the island nation of Tuvalu. If I understand correctly, a company did a deal with the country, but couldn’t guarantee registrants what the yearly registration fee would be. So some people paid big money (thousands) and are worried that that’ll be the yearly fee. Others have been reluctant to register. Unfortunate but true.
Regardless, I’ve registered 3-4 or myself, and one uses clever wording – if I do say so myself – in a popular blogging niche. (Sorry, won’t reveal it until the site is ready to launch.) My feeling is that if I can develop some screencast how-to tutorial videos for it, I could probably sell it for 5 figures next year. But without any content, the domain may go unnoticed. (You have to weigh several factors before you decide whether or not to develop a domain.)
One other trend I’m seeing is that more bloggers who are or want to become Pro Bloggers are getting “vanity” domains. These consist of their name and .com, .net or .biz, depending on what they do besides blogging. Some use a variation of their name. A domain name can be a personal brand, whether you use a .com or a .name TLD.