It's not about "not telling you the truth"--it's all about the inherent complexity of distributed systems. Might sound counterintuitive, but deletions are not easy to implement, and are very often deferred (obviously this doesn't apply to the image mentioned in the article).
For sure he's gutsy, but venture capital today means mostly "putting large amounts of money into startups that have yet to become businesses"-YCombinator demo day is the most fitting example that comes to my mind right now.
At least it's a breath of fresh air... no disruption just for the sake of using a buzzword--rather money poured on a project that has a faithful community, and with some niche design choices.
Reminds of anything? Reddit!
"Annotation eventually belongs in the browser." Couldn't agree more.
Endless comment streams proved to be of little if no value. Rap Genius is a glaring example that annotations (when designed and user properly) have way more potential than comments. The big money investment on Rap Genius just seals the deal, and pave the way for a Web where annotations are first class citizens.
Hope all the browsers will jump in the bandwagon very soon.
Google built something similar years ago--not a direct competitor to RapGenius, but rather a generic annotation platform for the Web.
Guess what? It's now discontinued: http://www.google.com/sidewiki/
It's not trivial to build annotation platforms that are both compelling and easy to use. Hat tip to RapGenius!