Majestic SEO has been in development for several years now. The team which I am part of has been working hard to try and publish the best index in the world. Alex who is the founder has recently published a page on the project website that compares the SEO project to other competitors. It is pretty interesting to see that the project is very competitive and is on its way to compete with Google. Please check out the link below and let me know what you think of the information.
Majestic SEO Comparison Web Page
http://www.majesticseo.com/research/competitors-analysis.php
But chart on this site is only until to 2009, would be nice to have a comparison for 2010/11. Still an impressive amount of Data.
Now only fulltext is needet and someone could create a nice Searchengine using Majesticseos Pagerank algorythm.