Not interested at all. The Jet Black is pretty sexy, but other than that, I'm not into a larger phone, and the only reason I see to upgrade compared to what I have now would be for the camera in the Plus, and I'm absolutely not interested in a phone that size.
At this point I'm content to hold out until next September to see if Apple offers a new 4" phone. If they offered a premium upgrade in April again next year, I'd possibly upgrade if the design were similar to the 7. The rumor of the all glass 2017 iPhone does nothing for me, so no need really to wait until September if there's something I like next April.
But realistically, I'm not sure what they could add to the SE that would make it worthwhile that would fit inside the case, considering the stink they made about interior space being a reason to eliminate the headphone jack. So any 4" upgrades are not likely to take advantage of all the 7 has to offer anyway.
But the removal of the headphone jack is reason enough not to upgrade for at least 6 months to wait for the market to catch up to Apple. Sadly Apple botched the headphone jack removal completely, without enough solutions in place to address several common headphone jack use cases. So until Apple gets this sorted out, I'd rather not own a phone in which I find out only after I have it that I can't do things I was able to do before.