It is almost no different. Many people have failed to understand for years now that domain names ARE the real estate of the Web. Only they are more intriguing than simple real world addresses like "1234 First St.", that carry very little value. (Of course, even in the real world, some addresses have inherent value, e.g., 1234 Rodeo Drive).
But domains are far more interesting as real estate addresses go, because they have not only 'real value' (the revenue they produce) but also 'marketing value' (their inherent meaning).
webwork's excellent posts from years ago still apply.
Domains with real/tangible value are the easiest to put a concrete price on, since real value involves type-in traffic, which involves revenue. Once you've got revenue, you've got a way of valuing things that even Wall Streeters can appreciate. And indeed, the business people are bringing more structure and transparency to this market by the day. Recent highly publicized sales of domain portfolios have established a new benchmark for domain name value: roughly 8X revenues. (That's right, revenues, not earnings.) That ought to tell you something about the perceived value of domains in the current marketplace, though it is not necessarily predictive of future values, any more than stock valuations are predictive. What's interesting is that this sort of valuation goes so far as to employ the same sorts of financial valuation and future discounting that is used to value other financial instruments. These days, it is as easy to value certain classes of domains as it is to value tax free bonds.
What is interesting this time around is that the Web has come into its own, and isn't going away, so there is reason to believe that domain name properties and portfolios may well hold their value, more or less.
So, do you have a domain that's generating $500 a year in reveunes? If so, it's probably worth about $4K right now, give or take.
But, what if you've got a domain that has potential branding power, or is sharply focussed as a generic (LargeBlueWidgets.com), but doesn't necessarily generate much revenue? Well, if the domain generates more than $7 per year, and you think it has potential, why not hold on to it? Hey, it's breaking even. The only question is, when and how to sell it.
As noted before, most domains sell themselves. Unless the domain is really high profile, industry stats suggest the most important element in the sale of a mediocre domain is simply making it clear on a landing page that the domain is for sale. Advertising 101. ;-)
At what price should mediocre domains be sold? Clearly that's up to the seller. If you really want to move a domain, make the price appealing ... perhaps something in the $70-$200 range. Most buyers can afford that.
If you care about making serious money though, you'll need a LOT of those sorts of domains to support yourself. ;-)
OTOH, let's suppose that you don't want to sell your cool (but not very valuable) domain for a couple hundred bucks? That's OK. Just be prepared to lose a little money, break even, make a little money on it each year, etc., until a passionate end user comes along, who must have your domain. That'll happen about once every 5 -10 years. But it does happen, sometimes.
One more thing, regarding pricing. In this market, the old saw that a seller must never give the first price quote does not apply. In fact, it's easy to spot a newb who's behaving that way...
Virtually all of those who are making money in this market know exactly what they are doing, where they sit in the seller/reseller chain, and how much the domain is worth to them. As a seller, knowing how much a domain is 'worth' is completely relative to your one's one business strategy. IF you don't get that, don't even think about trying to make a serious buck in this market. ;-)