Absolutely. The right thing to do is declare if it was a paid review or promotional consideration. However I'm sure most EEWeb readers would be smart enough to work it out for themselves.
The minute I need to start worrying about a website that supplies technical information is playing loose with the truth just because someone offers them some money is the minute I stop looking at the website. This one example might be obvious, but why should I have to start guessing the validity of a site that presents itself as an authority. I have only so much time to read things and glean the information. If I need to research everything that is said to make sure it isn't being distorted by money, then the place is a waste of time.
The guy who did that review, and the owner(s) of the website should be ashamed of themselves. They have lost all credibility with me. It should not have been called a review but rather a paid product release summary.