I read
this,
this and few more posts..
BUT..
..Favorites give us option to make just one group.. Could u implement option so we could make new groups..like friends, family, work partners, my birds

or whatever we want.. so if I forget partner from work name instead of look for his name,number or contact info throught whole phonebook, I will contract search list just to group named "work partners".. Or if I wanna give new email address just for job colleagues and I will send messages just to whole "job colleagues" group so no need to sms spam my family and friend cause I use old mail for them..
I think u got the point why that could be usefull..
keep developing awesome progy and listen to your customers needs..

cheers

10q