There is a new interesting publication at http://www.hpl.hp.com/personal/Vinay_Deolalikar/Papers/pnp_preliminary.pdf
that discusses the relation between P and NP problems. This problem has been defined as a Millennium problem and the solver is will be awarded with $1M prize: http://www.claymath.org/millennium/.
We will soon see whether the proposed solution will be accepted and stand still to the arguments...
Keep tuned.