I feel I have to add some perspective here.
As one who regularly helps promote sites in Google and other engines I can honestly say I know what it takes.
While having new content regularly appear on the site is a great idea, unless its written properly and compelling not many people will link to it.
You see links are what drive Google popularity - ultimately the site with the most links will rank the highest. Therefore
link building is a must. It must occur on an ongoing basis for your site to rank highly.
Now I know I'm greatly over simplifying the issue but at it's core links are the key to google rankings.
However the picture does get a little muddy when you realize that the best links are those google considers quality links.
In other words, while a high PageRank link is good, it is better if it's from a related or relevant site to your own.
Let me illustrate with an example: If you sell vacuum cleaners on your website, a link from Microsoft won't help you as much as one from Beam. That is because Microsoft is neither relevant nor related to you, however Beam is, so ultimately that lower PR link from Beam is worth more to you than the higher PR Microsoft link.
Now, that being said, it doesn't mean you should only go for sites that are related to your own. After all, that will get very difficult over time.
The truth is, almost any link you get will help, it's just the degree in which it will help. As I said above, while the link from Beam would be worth more to you, in fact the link from Microsoft is also worthy because it will contribute to your overall link popularity.
Consider link building like comparing 2 retailers: Walmart sells much more product at a reduced margin. However because of all that volume, their earnings are high. A smaller store may sell less, but at a higher profit margin per unit. Their net earnings at the end of the year can be similar to Walmarts with less units sold.
Link building is very similar - you can get the same effect from 1000 "so-so" links as 100 "good" links, and 10 "exceptional" links. The question becomes, what does Google consider "so-so" "good" and "exceptional" (these are my terms, I don't know what google calls them

).