There was an e-mail on the Wiktionary mailing list where a comparison was made between the English language Wiktionary and OmegaWiki. It was based on an analysis by Zdenek Broz. It compares the number of translations between the two projects.
The numbers may be right, but there is so much more to the English Wiktionary that it should not be reduced to such a numerical comparison. There is the Wikisaurus, there is a lot of etymological information, frequency lists, rhymes and most relevantly there are a lot of people who make it a great project.
It will take a lot more work before OmegaWiki can include all the information that is in en.wiktionary and it will take even more work before this information will actually be in there. I think this may happen but we do not need a competition for that. Both projects have there stong points and when we are able and willing to learn from each other it will be awesome.