Rift was "4" on the chart for 2-3 months before plummeting down below the numbers 3-4 of the MMOs on there held for years, and kept falling. By your logic, Age of Conan was a "good game" (believe me, other than lvls 1-20 it wasn't), which has the same growth and decline, and had waaay more subs at it's peak. It too went f2p.
Sadly with F2P, population counts are worthless because every account is technically "active". It's not the greatest measurement by any choice, but riftgame.com's unique visitor count may show that all F2P did was give Rift a bump in it's pop before dropping again.
http://traffic.alexa.com/graph?w=340...u=riftgame.com
http://www.alexa.com/siteinfo/riftgame.com
Even Yoshi himself said that all f2p gave was a quick drop of cash, but not only reduced the quality of content, and made developers keep creating items to sell for more funds, rather than things like raid encounters and locations. A p2p MMO going f2p is just a mark of failure, and done due to the developers needing to pay back their investors quickly.
An MMO shouldn't strive for being "good" for 2 months and then calling it a "good run".
Compare to WoW and EVE, and you see the website hits follow the MMO pop counts.
http://traffic.alexa.com/graph?w=700...9&u=battle.net
http://traffic.alexa.com/graph?w=700...=eveonline.com
WoW Pop Graph: http://users.telenet.be/mmodata/Charts/Subs-1.png
