It's down for me as well:
"This page (
http://play.pokemonshowdown.com/) is currently offline. However, because the site uses CloudFlare's Always Online™ technology you can continue to surf a snapshot of the site. We will keep checking in the background and, as soon as the site comes back, you will automatically be served the live version. Always Online™ is powered by
CloudFlare | Hide this Alert"
Can't log in, though I can see the chatrooms, etc. My phone which has a different IP, also cannot connect. Nor can a few of my friends.