When it's done
I tweeted Joe Belfiore about it, and he replied that we need to get on the devs to let them know we want it. If we want our favorite apps on our (new) favorite phone, we need to look beyond the forums.
In the meantime, check out lomogram. It's a holdover from wp7, but it has the same types of filters and effects that instagram does, but with more flexibility. It's more usable than many of the android clones I used to use. pretty much snap, crop, pick a filter, pick a frame and share, including to fb, twitter, tumblr, and flickr. If you're looking for the social side of instagram, that will have to wait, but the picture taking side is already here.