vim-outdated-plugins
                                
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                        Add support of popular status lines
Also just the normal built-in vim statusline. Maybe do this by asynchronously updating some global variable at startup?
EDIT: Looks like you already do that... g:needToUpDate
Also, shouldn't statusline functionality be responsibility of the end user?
@SicariusNoctis Yes, it's optional, but if this can be implemented, why this shouldn't work out of the box?)