It seems like backlinks do not play such role as used to be

Google stop promote websites through links. This is obvious. Everyone who has sufficient fund can bring his site in top. Was it fair? No. If you have a good site with proper content visitors will be more interested such site than visit well-paid but not relevant one. There is only one way now:One domain - one keyword. This scheme can be work for next couple years sure.If you have 30 keywords start 30 webs. I am sure you will spend much low on promotion all of them than you will promote 1 web with 30 keywords.
P/S If you want to use links they must be relevant and restricted numbers. No FFA, no directories. This is my point of view

 

use subdomains if you think this will help you.

 

good point however domains are more safty

 

Is this just your opinion or a fact?

 

Google hasn't stopped ranking sites largely on link analysis, they've only gotten better at analyzing the quality of each link.

 

this is a fact from my experience. I have webs for each keyword ( 34 in total) and can see how they are developing. To get position 14 in Google ( domain july 2007) took me 2 mnths and $30

 

PR is not main reason to be in the top anymore. I use backlinks without paying attention to PR. I check only ALEXA, because backlink now effect only traffic

 

One should only buy links for traffic, lest they waste their money. However, the ones that are given naturally, as an endorsement of a page, still count very much toward search position. Some, probably even most, paid links still help this way, although the writing is on the wall for them.

And then position #14 obviously depends on what key phrase, what data center you queried, and so on.