I prefer to use Maniapub than to make topics on this forum and others to advertise for my creations. It is probably less efficient but I think it is better for the community because it's less intrusive (i didn't test the new maniapub location). It is also easier for me and funny to make ads. If it works it's fine, if not it's only a game. I don't want to spend a lot of energy to promote my creations.
For skins, models, video or maps we know where to find it. But for title packs, blogs or contests it could be useful to be seen directly in the game. For example, I discovered a lot of stuff with Manianews. A problem could be a nice ad with poor content. But don't forget it's not like in the real life. Here, ads only talk about our game
