Battlefield 2 (Released 2005) has supported 64 players from day one. However what you say holds true only for consoles. At numbers over 16, I would say a dedicated server is required if you don't wish to eat lag all the time from the host's computer/console having a heart attack.
And with the servers that CCP have (one of the most powerful non-military server clusters in the world I believe), I'm sure they will have no problem serving it.
It's all a matter of efficiency, servers and available bandwidth. <!-- s:ugeek: --><img src="{SMILIES_PATH}/icon_e_ugeek.gif" alt=":ugeek:" title="Uber Geek" /><!-- s:ugeek: -->
Also - 800 posts! <!-- s:lol: --><img src="{SMILIES_PATH}/icon_lol.gif" alt=":lol:" title="Laughing" /><!-- s:lol: -->