I could be completely wrong on that, but I thought it went Pern/Dune, then Amber, then a pause, then Masq and GarouMUSH, then Elysium/Amaranth/City of Darknes, then a sudden deluge of WoD MUSHes.
When I joined Amber, the RPG wasn't out yet.

I am reawakening a long-dead thread, but I can clear the timeline up, since I was involved in all of it. 

PernMUSH was founded in January of 1991. AmberMUSH was founded in November of 1991 but did not open to players until the spring of 1992. The game opened after the DRPG was published (the DRPG was published in 1991), so Finndo et.al. and your play of the game definitely post-dates it.  Dune post-dates AmberMUSH by quite some span of time. (Belgariad MUSH, where Javelin/Paul got his start, dates to February 1992, and if I recall correctly, Dune was founded in early 1993, as it post-dates the closing of Belgariad in November 1992.) Masquerade and GarouMUSH developed independently of one another around the same time. Elysium came next (mid-1993), and then everything else.

Sadly, AmberMUSH is functionally dead now. But there's a new game, Chronicles of Amber (amber.genesismuds.com 8810), http://amber.genesismuds.com/ that has quite a few players.

I thought there was a Dresden Files MUSH around somewhere, too. Whatever happened with that?