Yep...I don't think there's any coincidence that the club have upped the stakes just before the January transfer window as that's when his value will be at his peak in his current contract cycle. Wait until the summer and we'd get significantly less I reckon. In other words, I wouldn't be overly surprised if we let him go in January to maximise the profit. Of course, the downside of that is that a replacement will be much harder to secure in January compared to the summer....
(having said all that, now cue Ings new contract accouncement next week!)
edit: actually, has he got one or two years left on his contract next summer? If two years then maybe there won't be such a differential between January and August. (I was thinking maybe he only had a year to go after next summer)