Hi Cosimo,

how many emails you'd have to send if everyone with karma 10 or above

Filtering out the users with below 10 karma would make around 5007 emails.

OR with forum activity within the last six month would be able to vote?

Unfortunately we don't have this information, you should contact Reggie Suplido about that. (the guy behind talk.maemo.org)

Best regards,
Riku Virta
Nemein