I guess I'll be in the minority and say thanks for a thorough poll!!
Of course, even as long as this list is, there's got to be at least this many more that could be listed as well. However, I have my doubts that any more than 1 or 2 of them would rank higher than the top 50% listed, which is really where the interesting results are.
Although the top choices are probably not surprising if you think about it, since popular, well-known authors are... well, popular and well-known.
But comparing the two polls (under 25 and over 25), it is nice to see that Tolkein is tops in both. Even if in my gaming I like to branch away from the traditional Tolkein-esque fantasy, it's still good that some classics are eternal.
Plus the biggest difference between the two poll results (at least as of now), is the older than 25 year olds appear to be wider read. Not too different in relative popularity, but the individual percentages are quite higher for the older crowd. None of the authors dropped in percentage and several (Vance, Leiber, Howard, Moorcock, and Brooks) had huge percentage jumps of 26-37% with the older crowd.
The largest differences in relative popularity are Pratchett does much better (relative to other authors) among the younger crowd at #3 author to #7 wth the older, and Leiber does better among the older rising from #8 to #5. The rest are within a place or two with Tolkein and Rowlings #1 and 2 in both. (Again, at least of the standings right now, but once it gets close to or over 100 voters, these polls don't shift very often.)
Fun stuff!