As stated in the title, when going to the home page, could it be possible to have the input focus in the search box since this is the place most users go?
Since there's only one input field on the main page, it's not a 'bad' idea. If there were more than one input field, I'd be highly suspect. I agree with Bill the Lizard on this subject.
I would respectfully say this might not be the best idea. Its one of those things that seems good at first glance, but ...
First, there seems to be one big (possibly unfounded) assumption there - and I have to ask:
Do most people go to the search box?
How do you know most people didn't get here via Google and are already on the question they want? How do you know that the bulk of the people who go straight to the home page aren't the folks looking for something to answer rather than something to ask? Just sayin'.
Also, are people really going to be that o.k. with the site deciding where their focus ought to be?
I agree with AnonJr. I am used to being able to hit the backspace key on my keyboard in order to return to the previous page. If a textbox has focus, though, I can't do this (I just delete something I never typed).