I have tested exactly this some time ago, at 3 different domains and about 12 keywords in total. I sent about 1000 wiki links total to 20 web 2.0 that were tier 1. (So in average one web 2.0 received 50 links).
Links were from all types of Wikis - Wika, MediaWiki, Macos wiki, wakka...
The results - DISAPPOINTING.
I do not recommend this strategy, similarly to not recommending using wiki's at all. However, you can do your own test and maybe surprise me so I finally will see something positive about these wikis...