On one Crea8site Forums thread, Barry Welford asks if size is a factor in SEO success. It seems from the results that bigger sites (1000+ pages, according to him) have biggest (45%) success. Smaller sites could still be improved upon, according to 27% of the respondents, and 18% actually find success with a sub-1000 page site.
In the meantime, with such few respondents (I should have mentioned that only 11 people have responded), you can't gather that much from the poll, and forum sentiment echoes that thought.
Regardless, EGOL has some interesting feedback, and I will follow that with my own experience:
I think that the measure of success is not really in how big the site is but instead with who is running the site. I have a 5000 page site that is doing great and a five page site that is doing great.
Recently, Technorati released its state of the blogosphere 2008 and Muhammad Saleem noted that high quality is still king. I'm in agreement here. My "small" (~280 pages) blog is doing darn well.
Forum discussion continues at Cre8asite Forums.
This post was written earlier and was scheduled for September 30th.