Scammy, deceptive ads have been in the hotseat this week, as earlier MySpace and now Facebook have made commitments to track down and eradicate misleading offers and survey-related ad scams.

Social gaming applications in particular are being targeted for permitting certain types of scammy ads, that typically persuade users into contracting for services without disclosing costs up front.

In a social game like virtual farming sim Farmville, for example, users can either spend real money to buy virtual goods, or complete offers and surveys from partner companies in exchange for virtual credits. The trouble is, some of those offers include “opt-out” riders that enroll the user in some sort of paid service or subscription, and require action on the user’s part to avoid misleading charges.

MySpace CEO Own Van Natta earlier characterized these “opt-out” type of offers as misleading, and announced a change to the Terms of Use to clarify what’s acceptable to both developers and users. Popular social gaming company Zynga also posted a statement stating a commitment to w