Congratulation for the awesome job you did this year managing and developping your groups' plug in.
We're about to buy paypal plugin but i'll try before to combine Groups with the 'social login' plugin (http://wordpress.org/support/plugin/oa-social-login) before. Only just facebook login interest me at the moment.
By the way, I'd like to hear about you on this topic. Did you already plan it in your road map ?
Looking forward to hear from you.