Dave Winer has some cogent critiques of the idea that companies can register their trademarks as new Top Level Domains (TLDs), from an intellectual property perspective. However I think the danger is more pernicious than that – allowing deep-pocketed corporations to create new TLDs at will risks the destruction of the Internet. In a nutshell, why would Google or Microsoft even bother with www.google.com or www.microsoft.com when they can simply use http://home.google or http://home.microsoft? Ultimately you will see entire ecosystems vanish behind these TLD-walled gardens. Forget about gmail.com; now you get redirected to http://mail.google. Take this further: these companies make browsers (Chrome, IE). So now if you’re locked into the walled garden of Gmail anyway and Google says “use Chrome, you don’t have to type http:// anymore” and IE users accessing Gmail see a moderately-degraded experience, then there will be forced migrations to ecosystems that don’t exist right now. Facebook is the worst offender already; imagine if they got into the same game with Opera or even worse allied with Microsoft/IE.
It can get worse. There are numerous limitations and flaws in the HTTP protocol since we have shoehorned all sorts of functionality onto what was originally just a hypertext linking platform. And support for HTTP starts at the browser. Today it’s already hard enough to write webpages for all browsers, and designers can’t code for the latest and greatest CSS/HTML spec and be confident it will Just Work. Imagine if Chrome decides to create a new protocol, g://? shorter, saves you characters on Twitter, built-in URL shortening, and much faster handling of video and pictures. Built right into Chrome! Interoperability between browsers itself is at risk here if the fundamental communication protocol itself starts to fragment; we’ve seen it happen already with HTML and CSS and browsers, but with custom TLDs the incentive to do worse will be irresistible.
The key is the ecosystem. Apps have shown us how companies move away from open protocols like RSS towards custom and closed APIs. TLDs will just accelerate and worsen the trend. Eventually your browser will run heavily customized and feature-extended HTML, with an optimized variant of HTTP that works best with the ecosystem it was designed for (be it Chrome/Android/Google or Facebook/Microsoft/Ie or Apple/Safari/iOS). Try to do anything outside that ecosystem and you’re forced back onto the “old” tools that will be slower and more unpleasant; sure, Hotmail will work on Chrome, but if you use IE it will be so much easier… switch! (to quote the Oracle of Pythia, “All this has happened before. All this will happen again.”)
Remember the old days when if you were on Prodigy or Compuserve, you couldn’t email someone on AOL without a complex extra header? We could be looking at the same thing, with the Internet. We will have to call it the InterIntranet.