We used MoreVisibility, and so far I've been pretty happy with them.
Many
SEO companies will charge 15-20 grand just to go through your pages and redo your meta tags, and hand submit to a few engines; that is a total ripoff. You could pick up a book at Barnes & Noble for 50 bucks and spend a couple days and do it yourself.
When all was said and done, I think we paid about $3000 for them to review our site and set us up with their XML feed program. They gave us a comprehensive report on what needed changed, and we implemented the changes. That was fine with me, no sense in paying someone else several more grand to just change some text around.
Then they worked with us to prepare a speadsheet of the top 25 keywords we should target, the page we wanted them linked to, the title, description, etc... From what I understand, they then provide this via some kind of XML feed directly to many major search engines (not including google).
We get charged a flat rate per click on all the keywords, there is no bidding. There also seems to be MUCH less click fraud through this system, and most of our listings from them show up in the regular search results, not PPC areas. Our monthly click thru costs are generally half of what we spend on Google.
As an example, do a search on AskJeeves for "online degrees" and we are #1. Do a search on MSN for "online degrees" and we are #6 (this varies throughout the day as MSN seems to switch their results at different times of the day).
I wouldn't call their service miraculous, but so far it has been very helpful to us, and worth the cost - considering it's very easy to drop even more money in a month on PPC campaigns that provide much less roi and alot of false traffic.