if you take money from a company and review their products, disclose the conflict of interest. This is fairly simple. Most new bloggers can understand this and most new bloggers aren't going to get paid for writing reviews anyway.
Why do you see this as a problem ?
Perhaps we have fundamentally different views on the role of the government in regulating speech. I agree that disclosing conflicts is desirable, and I think that people should behave ethically when reviewing products. However, I'm not sure why you feel government intervention is necessary here.
Anyway, I'm not worried about the regulation bogey-man here. New bloggers aren't going to be paid by companies to promote their products. If they are savvy enough to get a paid contract, it shouldn't be too difficult for them to publicly disclose their conflict of interest.