Echoing the thanks, here! Got it loaded and installed. I'm not noticing a lot of changes so far, although it seems like the Prehistoric era techs are coming a bit faster than they used to - about every other turn on the 1999-turn game speed. (I'm probably going to wind up wiping the continent of the other four civs - only Kublai has got a second city at this point, while I've just achieved Sedentary Lifestyle, established my fourth city, and am planning for my alpha strike against my vic... er, neighbors.)
Edited to add: Okay, now I'm starting to see the increased challenge level. I'm still the tech leader by a fair margin, but I'm not quite halfway through the Ancient Era and the other civs (some of whom are not yet beyond Sedentary Lifestyle) are starting to set up additional cities. Kublai is up to four (compared to my five, soon to be six or seven), Magrete is up to three, and Solomon and Menzies are at two. Under previous revisions, I would normally have had about half an era's worth of lead on them, but currently I've got one, possibly two rivals snapping at my heels, and all of them closing in on my borders and making further expansion... problematic. I'm thinkin' I'm gonna hafta be takin' back some leibensraum here in the near future...