PR is also used (at least, by me) to establish that the place has been around a while. It isnt the only factor, but I consider a site with PR3 to be more trustworthy than one with PR0 when doing any business at all.
I always thought PR determined how popular a page was... not how many quality backlinks that you had...
In an ideal world, they are the same. The more quality backlinks your page has, the more popular it is.
You think that's good? I got a PR4 for a domain with a 403 forbidden and zero backlinks. Got rightly set to zero after a couple of months. Did come across this pagrank chart a while back but obviously can't vouch for it's accuracy.
PR is all about backlinks. It has nothing to do with content. If you want to only increase your PR, get backlinks from sites with as high as PR as possible and with the fewest amount of outgoing links on the page. You only need one backlink from a PR5 site to get a PR4 (assuming your link is the only one on the page). If you want to help your rankings, make sure the backlinks are from sites that are related (same sector) to yours. PR is calculated internally by google shortly after it finds the backlink. It will only show in the toolbar when google does an update. By the time the toolbar updates, your backlinks have already been factored in to rankings. Toolbar PR is always a look at the past. You cannot have PR unless you have backlinks. Google won't even index your site without a backlink.
Not necessary The PR value we saw on the toolbar and calculator is only updated once per 3 months. Google updates PR in the backend reguarly. Therefore, a PR 0 page on your toolbar may be having a PR 5 at that moment Are you sure? Source: http://www.google.com/support/webmasters/bin/answer.py?answer=34397 To get a feel of how the formula of the PR looks like, refer to the paper from the Google's founders: http://www-db.stanford.edu/~backrub/google.html
I am not 100% sure about indexing if you just submit a site map because it is something I have never done - but I believe they will not index you without a backlink. I know that if you just submit your url to google, they will not index it without a backlink even though they are aware of your site. You can't have PR without a backlink and links are such a major part of the google algorithm, that you aren't going to rank for any remotely competive term without them - so it would be pointless to only rely on a sitemap. The purpose of a sitemap isn't so google can find your site, but to find all the inner pages. I have never seen an indexed site that doesn't have a backlink. People think that because google isn't showing a backlink, they aren't aware or counting it. Google only shows a fraction of backlinks to prevent people from trying to duplicate incoming backlinks from a top ranking site. If you do a search on Yahoo or MSN, you will find a link to your site if it is indexed by google. Every site will eventually get a backlink because there are sites that publish new domain registrations - so given enough time, google will find your site.
Is this really True? Because I got a few links only but most of them are from big sites like Boing Boing and SlashDot. Don't know if they count tho.
PR passes from the page where your link is. It doesn't matter if the site is a PR8, it matters what the PR is only the page that has your backlink. Look at the source code of the page and as long as it doesn't have a "no follow" tag, it should pass PR. PR is divided between all outgoing links on the page, so it there are 25 outgoing links on the page, a link to your site will only pass 1/25th of the pages PR to your site. If you have the only link on the page (unlikely), it will pass 85% of the PR on that page.