That's like someone linking a 37signals blog post and complaining that they don't tell you what 37signals does in every blog post. It's called going to the homepage. And I'd be surprised if the majority of Hacker News didn't know what 37signals is, and likewise with Balsamiq. Peldi's like one of the most active and well-known entrepreneurs here.

If you don't know what Balsamiq is you probably haven't been paying attention for the past year or so, or just don't read startup news all that often. Although they're not as well known as 37 signals, anyone that wants to start an internet business should know about them and their model.

Judging from the votes I would say 99.99% is probably a bit high.

As lame as the tone of this comment is, he's probably right that one should have a little intro about the product on blog posts like this. At the top and bottom probably, a small screen shot and a blurb/link would probably drive some sales and be informative for new readers.