If I have more than one link from a certain site, does this counted as 1 or the number of link back to my site?

What I want to know is for example a site have 10 back links to my site does links have density.

Which the following are not SEO friendly
http://Copywritingarticle.info
http://Brandingarticles.info
http://Fishingarticles.info
http://Networkingarticles.info
http://Creativityarticles.info
http://CurrencyTradingarticles.info
http://EzinePublishingarticles.info
http://Organizingarticles.info
http://Humorarticles.info
http://Presentationarticles.info
http://BookMarketingarticles.info
http://WineSpiritsarticles.info
http://MarriageWeddingarticles.info
http://CollegeUniversityarticles.info
http://Philosophyarticles.info
http://Depressionarticles.info
http://Leadershiparticle.info
http://PublicSpeakingarticles.info
http://BuildMusclearticles.info
http://Ecommercearticles.info
http://coachingarticles.info
http://interiordecoratingarticles.info
http://StrategicPlanningarticles.info
http://DebtReliefarticles.info
http://CruisingSailingarticles.info
http://Aviationarticles.info
http://HairLossarticle.info
http://DebtConsolidationarticle.info
http://Poetryarticles.info
http://Coffeearticles.info
http://DomainNamesarticles.info
http://SpamBlockerarticles.info
http://Gamesarticles.info
http://Pregnancyarticle.info
http://ResumesCoverLetter.info
http://Meditationarticles.info
http://Recipesarticles.info
http://CookingTipsarticles.info
http://positiveattitudearticles.info
http://GoalSettingarticles.info
http://Entrepreneurialismarticles.info
http://prarticles.info
http://Medicinearticles.info
http://CraftsHobbiesarticles.info
http://EmailMarketingarticles.info
http://CustomerServicearticles.info
http://Investingarticle.info
http://Outdoorsarticles.info
http://Hardwarearticles.info
http://FitnessEquipmentarticles.info
http://Successarticle.info
http://TimeManagementarticle.info
http://TeamBuildingarticle.info
http://spiritualityarticle.info
http://Securityarticle.info
http://SatelliteTVarticles.info
http://Taxesarticle.info
http://VacationRentalsarticles.info
http://Writingarticle.info
http://Happinessarticles.info
http://sitepromotionarticles.info
http://http://www.yogaarticle.info/
http://SalesTrainingarticles.info
http://Acnearticle.info
http://Softwarearticles.info
http://StressManagementarticles.info
http://Supplementsarticles.info
http://MortgageRefinancearticles.info
http://Motivationarticles.info
http://Relationshipsarticles.info
http://WeightLossarticle.info
http://CareersEmploymentarticle.info
http://Parentingarticle.info
http://Petsarticle.info
http://Beautyarticles.info
http://casinogamblingarticles.info
http://PersonalFinancearticles.info
http://PPCAdvertisingarticles.info
http://MobileCellPhonearticles.info
http://WealthBuildingarticles.info
http://SalesManagementarticles.info
http://Photographyarticles.info
http://GriefLossarticles.info
http://Innovationarticles.info
http://FashionStylearticles.info
http://Psychologyarticles.info
http://Diabetesarticles.info
http://Sexualityarticles.info
http://Inspirationalarticles.info
http://InternetMarketingarticle.info
http://Alternativearticle.info
http://politicsarticles.info
http://loansarticles.info
http://attractionarticle.info
http://holidaysarticles.info
http://Salesarticles.info
http://StocksMutualFundsarticles.info
http://BloggingRSSarticles.info
http://Exercisearticles.info
http://Advertisingarticle.info
http://Auctionsarticles.info
http://accountingdirectory.info/
http://background-code-free.com/
http://backgroundcodefree.com/
http://code-free-space.com/
http://www.multiplearticles.com
http://www.articlescopy.com
http://www.edpudol.com
http://codefreespace.com/
http://cpreview.net/
http://gqsky.com/
http://justforblog.com/
http://katropa.com
http://midnj.com/
http://uniquetours.org/
http://warehoused.info/
bankruptcy-articles.be
http://bookforsale.be/
http://cervical-cancer.be/
http://crones.info/
http://defecting.info/
http://ecommercedirectory.info/
http://extremer.info/
http://gamelans.info/
http://hungten.be/
http://issued.info/
http://iu.bz/
http://judiciaries.info/
http://lyricscollection.be/
http://outsourcers.info/
http://popular-search-engine.com/
http://reminds.info/
http://sablay.be/
http://sailor-moon.be/
http://submitsites.be/
http://trafficmadness.be/
http://wholehearted.info/
http://accountingdirectory.info/
http://www.cellphonetelephone.com

Is it true that back links from certain forum like this won't increase our PR? For example all my post have a signature linking back to my site.

yes backlinks from this site will increase your PR and backlinks however spamming forums just for links is never a good idea. Your most important links are still those relevant to your industry

__________________
Vote for your favorite SEO site and tell your visitors about this great place, please link to us http://www.seo-guy.com with the anchor text SEO and let them know how you feel

OKey I have lunch my site a month ago and get links to a lot of site but why that my PR still 0? How long should I wait before my PR increase?

__________________
busby seo challenge | Busby seo challenge

The PR bar has not shifted during the last two backlink updates so who knows?

__________________
50 Cent | Email Santa Claus Free