As long as type in traffic or "direct navigation" continues... domains do not need to be developed for traffic... and parking will continue.
What will you see in the future of parking?
You will see more parking services offer revenue sharing for people who click and buy. I have had some $35 insurance clicks on Domain Sponsor, and I am also getting some very high clicks on Fabulous on my "mortgage names".
Anything that increases revenue by a significant percentage will outcompete less profitable solutions. Over time, an active domain that involves and retains random users and makes them come back for more will be more profitable than a parked domain that tries to get one-off visitors to click on ads. The shift from PPC to revenue sharing is a separate development and it will probably affect developed as well as parked domains.
"This will be hugely popular for a while, then the whole Web 2.0 market will crumble as people tire of reading meaningless, unedited posts and comments." -Comment #8
"To be exact, about half of the advertiser’s payment goes to Google"
I've never heard of a parking provider on a 50% split, 70%+ is more normal. Even the smallest adsense for domains partner wouldn't be on a 50% split.
"and the remaining half is split, usually in unfavorable proportions, between the parking provider, e.g. Sedo, Namedrive, Fabulous etc., and the domain owner."
Ditto, never heard of a major parking co paying less than 50% "unfavorable proportions" isn't true.
"By doing so they can usually more than double a domain’s income as they are now dealing directly with Google’s Adsense and no longer with a parking provider who takes his own cut."
This is a load of nonsense, adsense pays a lower split to regular signups compared to what most parking co earn, plus adding content to a domain reduces CTR. A developd domain needs to see increased traffic in order to offset the reduction in the amount of advertising on the page (assuming everything else is unchanged).