The most valid poll for me, at least the one I trust the most is the polls of DWM readers who, as some people prefer, are more likely to have watched more doctors.
In the 2009 pre-Matt Smith Poll of 6700 DWM readers, the results were
David Tennant - 25.64%
Tom Baker - 24.73%
Patrick Troughton - 11.39%
Peter Davison - 9.84%
Jon Pertwee - 9.66%
Christopher Eccleston - 5.71%
William Hartnell - 4.69%
Sylvester McCoy - 3.88%
Colin Baker - 2.87%
Paul McGann - 1.60%
Unfortunately, as a McGann fan I've resigned myself to never see Eight anywhere near the top of a poll, as unfair as that is.
But when the next DWM poll is taken, I think David, Matt and Tom will both be on about 16% each and the order of popularity of the other Doctors will remain the same. I don't know much about these things, but that's my opinion
EDIT: Oh, and I should add, Billie Piper came third in the 'Best Companion' poll, behind Elisabeth Sladen and Catherine Tate.