Does anybody know what is google current algorithm or has a link to an article that describes it?
I don't think anyone truly knows except the people who work at Google. I can tell you one of the heaviest weighted factors in the algorithm is anchor text of incoming back links, followed by title tags and h1 tags.
Though The Exact Algo is never disclosed [ Otherwise it would not take any time for people to abuse it ] , but a friend of mine did an experiement on this... You may want to take a look at this page for the results that he got - http://www.seotown.com/showthread.php?t=100
The actual page rank is computed using a piece of maths originally discovered by Wei back in 1952 based on calculating the primary eigenvector of the connectivity matrix (which pages are connected to which others). There's a fairly techie page on it at http://www.mathworks.com/company/newsletters/news_notes/clevescorner/oct02_cleve.html
The benefit of using this is that the pagrank is purely a function of the reputation of the pages that link to you and doesn't include any special weighting due to header tags. Special consideration for header tags is entirely fictional and anyone believeing in it should be burned at the stake as a heretic :-)
The Google alogorithms is kept secret. Even the professional working in Google can not explained its algo clearly. They are asked not to leak any information outside. And the professional working on particular modules can let you know about only that modules.