It has been 4 for a year or so, how to improve it?

Links from better known sites. PageRank doesn't mean very much, but it's a measure of how many links point at you and what each one's quality is. And how many other links are on the page pointing to yours - the less the better. So in order to gain PR ( which won't help you that much ) you need more links from higher PR pages pointing at your site and little else.

amyangel - I believe we've met on another Forum in the past, as I remember your site(s) ... ForrestCroce is right, and this is something I've been harping on for over a year.

Forget PR; it doesn't mean anything anymore -- you need fresh content and excellent links back to you; but make sure they're "relevant" links to each of your individual sites.

I think most people will tell you the same thing - links.
PR is nothing but links.

Get more quality backlinks from trusted site.

Forum Posting and Link Exchanges

Originally Posted by solidghost

PR is nothing but links.

That's actually a pretty accurate way to put it. PR isn't a measure of quality, but it tends to be a side effect.

Yes,link exchange first

Create signature on forum then posting.