Mine is being deindexed or should I say, most pages are being placed in the supplemental hell. This is been happening for the last 6 months. I have over 90K pages in the supplemental hell and 6k live now. Tell me I'm not alone.
Google isn't going to deindex a site simply because it has vBSEO installed. You should look at other factors that are unique to your site.
Google is doing a complete makover. Many old links and such are being deindexed. You could say they are cleaning out most of the results. Make sure each page is unique and has good content
Why would you get deindexed for using vbseo that sounds mad and can't be the reason VB 4 the new VB doesn't need VBSEO though which VBSEO staff must be dirtying their pants over LOL
Yes, there is something strange happening to Google. Also VBseo needs to adopt to the new algorithm by Google.
actually, if I am not mistaken, it can result in de-indexing... If you have a long standing forum with thread urls like /showthread.php?t=1691049 that are now showing up as Is_your_vbulletin_with_VBSEO_being_deindexed you may need to be re-indexed. Though, I could be blowing smoke, as I have NO clue how that system works... but I guess if the basic url does not re-direct, then it could push itself into being 'non-existent' in the eyes of google. If it does, then it could be getting pushed into supplemental hell based on having two addresses? (again, no real clue what I'm talking about LOL ... just shooting out some possibilities?)
I don't know whether it is Vbseo or not but damn, Google is giving me the treatment! They have me asking for water by sign language.