I agree that exfoliating and keeping the pores clean help them to 'shrink', I use coconut oil on my combination skin and I find it sinks in nicely and doesn't make my t-zone greasy. I can't say the coconut oil has made my pores smaller but they seem smaller so I know it has had a negative affect.
Oh and the electric toothbrush method seems like a more hi-tech version of my facial brush (from The Body Shop)!