How to "remove" bad reviews for a certain keyword from the SERPs

There is not really anyway to remove them. What you will have to do is replace them by creating and ranking enough new sites to push them off the first page.

I would say the same: you can't get these comments off ! Your concern (your friend concern anyway) is about e-reputation ! The only way to reverse this is to enhance your e-reputation with more good feedbacks than bad ones !

Here are the best ways to get them "removed", easiest to more difficult:

1. Ask whoever put it up to take it down (if possible) Nicely asking might work
2. Turn negative into a positive. Respond to these complaints rationally. Even if you don't win him/her over, you might be able to show others that you're reasonable and the complainant is unreasonable.
3. Out rank the complaints with other sites. Many social sites allow you to have the brand/company name in the URL (twitter.com/BRAND, BRAND.wordpress.com, etc.) and with just a bit of SEO, those should be able to outrank the complaints
4. Seek legal assistance and start the legal process against whoever is doing it. Many times, a simple C&D will get people to give up the cause.

Theres nothing you can do and why should there be ? people are entitled to express their views about anything on the net, which can be a total pain if your on the end of someone who takes exception to your products or website.

If it made certain claims that warrented legal representation then maybe you could get it taken down, but even then its not easy.

Belive me ive tried in the past, best thing to do is just to work on your reputation moving forward and ignore the bad comments.

Woc

I think your best chance is to create about 10 blogs from High PR blogging platforms such Wordpress.com, blogspot.com, tumblr.com, typepad.com, webs.com, liverjournal.com, etc. . Post 3-5 unique and keyword-optimized articles in each of these blogs and then you point hundreds of backlinks to the blogs. That is quite a big undertaking because you are not just aiming to get 1 site to the No. 1 position but the aim is to fill the whole First Page of Google with allied/friendly sites. Can it be done? Yes of course! The only limiting factor is your determination and persistence to get these unfriendly sites off the Page 1 of Google.

We have done these type of things several times with success and that is why I can say with confidence that it can be done. Search for "zara clothing" without the quotes in Google US and you can see 11 of our sites in Page 1 and 2 .Here are the sites we created as some sort of experiment to see if our spun articles can rank in Google:

myzaraclothing.livejournal.com/
zaraclothing.typepad.com/
zaraclothings.weebly.com/
myzaraclothing.tumblr.com/
myzaraclothing.typepad.com/
zaraclothing.posterous.com/
zaraclothings.livejournal.com/
myzaraclothing.blog.friendster.com/
zaraclothings.blogspot.com/
myzaraclothing.wordpress.com/
myzaraclothing.onsugar.com/

Now the above sites have only 1 spun article and about 100 backlinks each. Imagine if you post 3-5 unique and keyword-optimized articles in these kinds of blogs and you point 500 backlinks each.

By the way, the above blogs were not created to displace an unfriendly site because we do not disclose information on clients for whom we did this kind of "displacement of unfriendly sites" service to protect our clients. However, this is exactly the same successful strategy we implement to displace unfriendly sites from the Page 1 of Google.