Thanks for your responses, George, Chris, and Wallace.
As several readers of this thread already know, and perhaps you three also, "Nereid" was somewhat active in PF, and also in
http://www.bautforum.com/index.php".
At least one mod, here in PF, thinks that "Nereid" does, indeed, have a PhD (I can dig up the post, if anyone's interested). However, as
http://www.thenewyorkerstore.com/product_details.asp?sid=22230", it is totally up to you what you consider Nereid to be, let alone what degrees she/he/it has!
As to reliable sources - wrt astronomy, astrophysics, and cosmology - one of my long term goals is to be able to offer succinct, accurate advice to the (no doubt many thousand, if not million) people who do not have advanced degrees in physics (or related field) yet who are genuinely fascinated, interested, attracted to, stimulated by, {insert your own phrases here} the reported research results (or other advances in) astronomy/astrophysics/cosmology.
My conclusions, so far, differ little from what you, collectively, have written.
In more detail:
* wiki: some pages are excellent, some are less than excellent, one must decide on a case-by-case basis whether to use these ... and the context of their use is also very important. More generally, this is the most promising direction for the future, IMHO, and so those who can spot the imprecision, inaccuracies, etc in a heartbeat have, IMHO, a duty to roll up your sleeves and fix them.
* popular magazines (SA, NS, S&T, Astronomy, ...): yes, they all have their strengths and weaknesses, and some articles are superlative (and some less so). Again, it's a matter of horses for courses: for example, the Lineweaver and Davis SA article on 'receding faster than c' (and other BBT myths) is, IMHO, one of the best popular pieces ... period (and you can always link to their more technical paper for those who want more detail).
* Q&A: PF is, without a doubt, head and shoulders above anything else. However, it's also rather cold and somewhat too technical. BAUT's Q&A is more accessible, and there are enough professionals there that few, if any, questions will be answered badly (in the end). AFAIK, there are no other fora that come remotely close to these two.
* books: indeed, but the range is vast - technical, accurate, etc to just plain awful ... it's another horses for courses, but the difficulty is recommending a book as the best way to answer a one-post internet discussion forum post may well miss the mark rather badly (so, in economic terms, is a poor allocation of scarce resources).
* arXiv: indeed, so many papers, so little time! Add ADS to the mix, and you're in seventh heaven ... the 'only' thing you need is to assist folk with decoding the papers, reading through (or past) the math (etc) to the key findings ... My key wish here is some way of identifying good review papers ...
* blogs, etc: there are several, which can help a great deal in terms of showing folk what it's really like ... and even some (such as CosmoCoffee and AstroCoffee) which do a filtering for you, in terms of papers likely to be interesting ...
* press releases: these vary widely in quality ... the most maddening ones, IMHO, are those which do not provide a link to the relevant papers (whether in arXiv or already published). To me, this is about the worst sin they could possibly commit, even worse than the sometimes infuriating hyperbole the marketing folk who had a hand in writing the PRs insisted had to be there. OTOH, they do provide a direct, powerful hook to get key points across, especially wrt 'the origin of the universe as a singularity' (for example).
So, let's welcome those who have curiosity sufficient to find a place like PF and ask questions!
Let's not turn the fascination and hunger off, even if the poster has (apparently) some quite muddled ideas, or has been reading too much of what's on crank sites.
After all, isn't the most valuable thing we can do is to convey some idea of the nature of the scientific method (wrt astronomy, astrophysics, cosmology), the rigour of the tests used (etc), the profound importance of critical thinking, along with the sense of wonder and awe we all feel reading the latest results?