I think GmailAssistant is a great piece of software.
But I would love to use GMailssistant not only with my GMail account, but also with my other IMAP accounts, so I will only need one notifier for all my e-mail.
Since GMailassistant uses IMAP to access GMail anyway, I think there is probably not a lot of work involved in adding this feature, while at the same time it would mean a great improvement in functionality.
Thank you for your interest in GmailAssistant!
I'm afraid support for general IMAP email services is beyond the current scope of the program, but I will keep your feature request in mind for a future version.