As smart as the Hacker News set may be, most people are not experts in the field and could do with a little context.

Also, Aaronson's a well-known computer scientist, so this helps establish that the result's both credible and important in the eyes of people who may not (forgive me) all be qualified to judge the paper on its merits.

Context: fair point. I can't say I'm familiar with Aaronson, however (of course I studied math and not CS).

"Well-known" in a particular field doesn't necessarily mean "household name"... do you know who Tim Gowers is, for example?

http://en.wikipedia.org/wiki/Scott_Aaronson

A lot of people might know him from http://www.scottaaronson.com/writings/bignumbers.html, which is the article about that topic.

edit: Okay, rereading this article I recovered an insight that leads to a truer reason Aaronson's worth linking to. It is not that he's a famous professor (he is) so much that he is, in general, a great expositor. Read that big-number article and tell me he's not.

The layman terms background and summary adds a lot of value for the non-mathematicians in the audience.