@Carl Hancock - I think you are right that the commercial theme page was used as a carrot to encourage the adoption of the GPL, a meeting certainly took place between Brian Gardner and Automattic before he made the jump, but there wasn't anything insidious about that - I don't think there was any direct gain for WordPress in having them move to GPL, it was more about stoking the pace of theme development by establishing a licensing environment that would allow themers to share innovations i.e. saving everyone the trouble of having to re-invent the wheel. This is good for everyone in the long-run but I don't think Automattic had any direct self-interest in mind, it was more about helping the nascent theme industry to get into line with the philosophy that has underpinned the success of WordPress.

You are also right that the quality of some of the 29 sellers listed in the commercial directory is not impressive. You can see how this might happen - I am not sure what the criteria for acceptance are but anyone can apply and, if you appear on that page, you are getting a high Page-Rank link to your website and, also, a certain percentage of people coming to WordPress.org to search for themes are going to make the very common mistake of thinking that themes you pay for must be better than free themes. Just by sheer weight of numbers, even lousy themers, touting low-quality knock-offs of free themes, will get a few sales. It would probably be possible to make a living simply repackaging free themes to sell to people who value the fact that they had to pay.

The scary thing is that a commercial plugins page would have the same problem, but magnified - at least with themes, you can visit a demo and see what you are buying, plugins are much harder to assess before you actually install them on your own blog.

The main problem is that it wouldn't just be companies such as yours, who have put a lot of work into their product, it is inevitable that every popular plugin in the free repository will be hastily copied and sold by someone looking to make a quick buck, once again harvesting dumb customers who presume that things you pay for are always better.

Some of these knock-off plugins will come complete with bugs and errors that the shady vendors will not be skilled enough to fix. Customers, having paid good money, will kick up a far bigger fuss than the users of free plugins. The WordPress project will receive a ton of flak, regardless of how clearly they explain that they are merely listing and linking to outside companies for whom they bear no responsibility.

The original plugin authors, who have spent years developing and supporting their creations for free, will obviously be upset to see a privileged spotlight given to people who have contributed far less to the community than they have, and this will obviously act as a disincentive to contributing further free work.

This is all entirely predictable, so, you can hardly blame WordPress for wanting to steer clear of that quagmire (Giggity-giggity).