No, actually, it isn't. You're quoting a piece of marketing material for chrissake. They handle 80% of all Bitcoin TRADE. As in Bitcoin-to-USD-and-vice-versa trades. Not Bitcoin-to-Bitcoin transactions.

You clearly don't have even a basic understanding of how Bitcoin itself works. It's a distributed, peer-to-peer system. That statement is analogous to saying "The Pirate Bay handles over 80% of all Bittorrent traffic." In reality, TPB handles exactly zero actual torrent traffic, and Gox is in no way involved in processing actual bitcoin blockchain transactions.

Like TBP, Gox is a convenient target for people trying to disrupt easy entry into the more robust distributed system that it provides access to. But if you already have bitcoins and simply wish to spend them, Gox could get sucked into a blackhole and it wouldn't affect you any more than a raid on TBP affects your in-progress torrent downloads.

Is there a limit on the depth of comments here? I can't seem to reply to cjh_'s adjacent post. Anyway, he's correct that it's possible to keep all your coins on a Gox-hosted wallet. I kind of forgot that people actually do that. It's a really terrible way to store your coins, even if you use a more stable/trustworthy service than theirs.

There are much better ways to utilize the convenience of a web wallet without handing all your coins over to some sketchy website, such as blockchain.info's wallet system.

Yes and No. You are right in that Mt.Gox doesn't handle 80% of all btc-btc trade.

However many use Mt.Gox as their wallet so the TPB analogy doesn't quite hold that far, as Mt.Gox being taken down would mean these people wouldn't have access to their BTC funds stored in that wallet.

I should have mentioned this in my original post, but I was sloppy.