For me it is a mix of all the above really.
If it is a publisher I like or the sequel to a good game or looks like it will have amazing gameplay I will preorder if I feel the bonus is worth it.
If it doesn't meet some of that criteria the pre-order bonus doesn't even come into consideration for me.
Once I know I am going to get something I figure I may as well pre-order. I am going to get it anyway so I may as well get it cheaper or with a nice bonus.
If it is a publisher I like or the sequel to a good game or looks like it will have amazing gameplay I will preorder if I feel the bonus is worth it.
If it doesn't meet some of that criteria the pre-order bonus doesn't even come into consideration for me.
Once I know I am going to get something I figure I may as well pre-order. I am going to get it anyway so I may as well get it cheaper or with a nice bonus.