All of the iPad-related stuff is under a non-disclosure agreement, so we can't really say much about what features the mail app there will have or not have. For what it's worth, the mail app on the iPhone doesn't support the sort of cross-app communication that the clip-o-tron depends on.
We can't make a blanket guarantee that every feature in the Mac version will appear on the iPad/iPhone. We do try to bring over the ones that are a) possible and b) important to customers' workflows.
The best thing to do here is to let the
support ninjas know that this feature would be valuable to you on the iPad; that way the team can take your feedback into account while they work on that version of the app.