In my view, meta.stackoverflow.com is a forum related to stackoverflow.com. That is, this is a portal/site dedicated to comments/improvements related to Stack Overflow. If this is so, why do I need to create a separate login/account for meta.stackoverflow.com?
StackOverflow sites, including meta, use openID. The same OpenID credentials you used to log in to StackOverflow.com should work just fine here at meta.stackoverflow.com.
If you use the same OpenID, you can associate your accounts in your user profile page.
Because the site/sites is/are messed up..
It makes little enough sense that a question one posts can get migrated to another site (e.g. serverfault) where one needs another log in to access that question. If the question can be migrated why does that account not work!
Like you said there is no reason why a forum on SO should have a separate log in.. maybe it was easier to code ;-)
If meta is for stackexchange not stackoverflow they should consider changing the URL to meta.stackexchange.com (which redirects here anyways).
Personally I think that the separate log ins is one of the worst features of SO..
I actually find it insulting that there is a notification system for stackexchange but not an authentication system for it! If you can give me messages from all accounts together then here's a crazy idea... HAVE ONE ACCOUNT! lol
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