what does the "Position in top 100 for allinanchor:" Look up in Google actually mean. For one specific keyword, i'm #28. So what exactly is this telling me?
Telling you there are 27 sites with more links than you for that paticular phrase. I don't use the allin any how, I prefer the inanchor: as you can combine inanchor: with intitle: etc giving you more control.
Allinanchor gives you like the others said above, an indication of your positionin regards to incomming links for that phrase ( like the welsh man said ). Allin Anchor for a keyword is a contributing factor for the SERP of that keyword. Depending upon the phrase it could be a major determinding factor. You will not go wrong getting closer to # 1 for allinanchor here is a good thread about SERPS on this forum http://forums.digitalpoint.com/showthread.php?p=3167#post3167 McDar.net has excellent tools as well, and proven track records. Info from this forum http://forums.digitalpoint.com/showthread.php?t=256&page=206