The recent repeated abuse of the term DDoS by ignorant members of the bitcoin community is misleading and confusing.

The first D in DDoS mean "distributed". There has never been any evidence of a distributed attack.

Server overload from heavy use of an application is not a DoS attack. A 37 transaction per second capacity suggests that MtGox simply cannot handle even moderate trading activity.

The frequent small trades that the exchange sometimes sees can reasonably be explained by bots trying to exploit the market in some way and not to attack availability of the exchange itself.