If you have been living under a rock and don't know the meta part of HN, then sure, it's an advert. As it stands, LPtHW has been the centre of a lot of debate inside and outside Hacker News with Zed participating in the comments on Hacker News as is his wont[1]. Zed has made the very relevant point of where the hell Python - or programming - newcomers are going to look for an introductory text that doesn't make them run screaming for the hills, something Dive into Python does. And because he is the great guy he is, Zed did more than oppugning in a back-and-forth Python discussion, but took the time and effort to release an, at the time, free, fantastic introduction to Python, using a very novel and didactically amazing approach.
The sole shop for LPtHW is on Lulu, and thus, this link - submitted by someone other than Zed - is a nice service to the people who know about the book - and might even have downloaded the free .pdf in its formative stages - and plan on getting it eventually.
Zed Shaw is one of us HN guys. Not an outsider peddling snake oil or an arbitrary product. He preaches the merry gospel of programming and hacking better than most of us will ever be capable of doing, and with no ulterior motives. If that isn't worthy of Hacker News, I don't think I know what is.
User popularity has little to do with what I wrote. :)
I think it's find to have a rule set, but rigid lines will rarely help when applied to real-life cases. I'm sure pg suggests using your own gut feeling and common sense when weighing the merit of a submission.
Hmm.. I think user popularity definitely has something to do with what you wrote. The user in question is popular for a very good reason, but that doesn't really change the fact :)
Personally, I think that if a post doesn't directly provoke conversation, maybe it shouldn't be posted.