Well gawsh - I used to believe that Isis, Sif, Idun, Hecate etc were Goddesses, but after that finely honed piece of debate I've totally changed my beliefs and want to convert.
Oh no, wait... I don't.
Meetings? Well, they vary - what I'm referring to is a gathering of Pagans involving some sort of ritual. Some of these rituals were simple pathworkings to get in contact with the essence of the God or Goddess we were specifically interested in - others were huge rituals with turning circles, chanting, incense, enormous bonfires, meadhorns, calls to the quarters and visualisations intended to attract the attention and call for the blessing of a specific deity.
My own beliefs are Asatruuar, but I also acknowledge the Gods of the other faiths - even though I don't worship them any more. What do I think constitutes a deity? Well, worship would have to be one of the primary constituents - I don't think people can worship something non-existent for very long, once a religions deity stops answering prayers and rituals it doesn't take long for a congregations heart to leave it.
Personally I blame the ancient priesthoods for the rise of Christianity in Europe - I think the whole of them, from Druids to Gothi, forgot that a priest is supposed to be a learned guide, not an intercessor.
Eon