Since this is getting rather heated elsewhere, I thought I'd split this off.
What makes something a *god* to you? What characteristics are essential?
Do they change, or are they stagnant?
What restrictions are there on who can worship this god, if any?
My POV (taken from that FAQ for Conair an Cheo I did a while back):
Gods are beings who have considerably more of the Divine essence within them than anything in existence on Earth, allowing them a greater intellect and understanding of the universe and existence. All gods exist; historically, they have frequently been placed into groups, and though They generally work within those paradigms, They are not restricted to them. No gods are omnipresent, omnipotent, infallible or all-knowing; though Their perspective is less limited than our own, they are capable of action and therefore capable of mistake. They are less prone to mistake, though, than misjudgment what a particular person will do. The Gods have no natural physical shape like humanity, nor do They fully reside within our plane of existence. They are capable of existing within a physical shape at Their will, which may or may not be human in appearance. They do, generally, have a form that They prefer, that humans have come to associate Them with.
I think that since They are capable of action, one could assume that They are equally capable of change. I agree with Jenett, though, that some things may change superficially but remain on a deeper level.
As for who can worship Whom; I think it is utter and total hubris for a person to make any claims as to who is and isn't allowed to worship a particular deity. In what manner, a person might have some right- as in, "you can't worship deity X in such a way with us", but to say "you can't worship deity X" is asking for trouble, imo. I'll let the Gods decide for themselves, thanks.