Should Pinterest Replace Tumblr for My Microblogging?

I've got a microblog problem. I don’t get too much time to pen fully formed stories for DadTherapy so I supplement by posting photos to my @DaveLikesCars Tumblr page which seeds the Twitter account etc. Then Pinterest comes along and offers a similar alternative.

Would it make more sense to put my micro blogging — which are mainly images of cars — on Pinterest with a far wider potential audience or stick with the Tumblr blog and it's giant display of its own?