Hey guys, I was wondering if using a popular theme that is used on hundreds if not thousands of sites would hinder my chances of ranking high?
It won't afect your ranking in the slightest - google or yahoo doesn't care if your text is the same font or shade of green as other sites. If it's a very common template you might lose a bit of credibility with visitors, but even on a free template you can alter the graphics easily enough to make it a bit more individual.
Using a popular theme won't affect your ranking. If it's too common, then you might not be able to leave an impact on the visitors.