This really isn't an ethical question. Let me explain my position:
1. Escapist Corp wants users because more users = greater advertising revenue.
2. Escapist Corp organises developer hype competition to amuse existing users and attract new users, pursuant to the goal expressed in #1.
3. Escapist Corp realises that allowing and even encouraging the competing developers to advertise the competition, they are effectively encouraging free advertising for themselves.
4. For this reason, they deliberately write the rules of the competition so as to not exclude such behaviour on the part of developers.
5. Some developers take actions that are perfectly within the rules (and this must have been intended by the competition organisers, they've had time to prevent it if they wanted) and consequently do better.
That some people are upset by campaigning is due to one of two reasons, one of which is a sub-reason of the other. The main reason is that they do not understand the point of the competition. It isn't to find the best developer. It isn't even to find the most popular developer, or even the most popular developer amongst Escapist users. The point of the competition is to increase ad revenue and user throughput at the Escapist website. Nothing more. The second reason is that people are upset at the inclusion and success of Zynga, a company that many feel doesn't make real games. I agree with this view, but it would only be salient if the tournament was about any more than mutual promotion between developers and the Escapist. The advertisers don't care if the people clicking on their adverts play Mafia Wars or WoW or CoD, and the Escapist certainly doesn't. It's all money in the bank, and Zynga have access to plenty of useful walking $ signs.
None of this is meant to be a dig at you if you are enjoying the competition, go nuts, have fun. It's just my opinion on the real point.