If the Palestinians declare a state at the moment, it will simply be another failed Arab state. At the moment, there is no real drafted Palestinian constiution, no parliement, no clear representative of the Palestinian population, and of course all the different factions continue to attack and assault one another for "complete supermacy" over the Palestinian people. The Palestinian issue nowadays is just to messed up and complicated, and it would be foolish to declare an independant state under the current political landscape.
The only way the Palestinians will truly be able to pressure Israel and the world community into accepting them as an independant state and prove that they are capable of operating and governing an independant state is through setting up independant democratic insitutions (with the help of other Arab states) and a drafted consitution (that would be the official consitution of any future independant Palestinian state). Further, the constiution must be adopted by all the different factions, including Hamas. Democratic elections should be held regularly with a strong parliement that integrates all the different representatives of the Palestinians.
There should be no attempt to violently force any Israeli settlers out of the West Bank, because it would only give Israel an excuse to abolish any attempt by the Palestinians to form an independant state. That should be dealt with through direct negotiations, and at the time, I believe that Palestinians will have garnered alot of respect and support from the international community.
That will probably never happen, but that is just how I see things should work out. I highly doubt it will, though.