strom - Actually, the replies mirror what I imagine the sales would reflect. I don't see the MRQ rules being a huge hit - not like the Conan introduction. There can be no doubt they have a loyal and fanatic fan base but it can't compare to the OGL D20 base already established.
Interesting argument. I hope you recognized the fact that the runequest forum has after 3 months time already approximately 10% of the amount of postings the conan forum has. And MRQ is not even out yet. So be not sure that only few die-hard fans are watching the release of MRQ very closely.
Of course d20 is played by many more people, but it has a lot more settings and worlds, so the D&D and d20 players which are also interested in conan d20 are just a part of the potential fan pool.
RQ was once no.2 on the RP market and could sell very well. Who is the potential customer of MRQ?
-the switcher (which is tired from other systems and wants to try something new, more realistic)
-the old RQ fan (there are many out there which would probably buy anything if it has the label RQ on it)
-the Call of Chthulhu fan which like to play a fantasy setting sometimes but dont want to learn an new game system.
-maybe even the Heroquest player would buy MRQ just to have the setting of the 2nd age Glorantha.
So dont be sure that MRQ will not be a hit. And the better Mongoose have done its job in modernizing and improving the system, the better it will sell.