I’m not going to do a report on this one as it is a) epic, b) unprecis-able and thankfully c) pretty much off topic for housing law. But anyone who, like me, is a bit of an equity hobbyist on the side, the House of Lords judgment in Yeoman’s Row Management Limited (Appellants) and another v Cobbe (Respondent)  UKHL 55 is a must read on proprietary estoppel and constructive trust.
The upshot is that
Proprietary estoppel requires, in my opinion, clarity as to what it is that the object of the estoppel is to be estopped from denying, or asserting, and clarity as to the interest in the property in question that that denial, or assertion, would otherwise defeat. If these requirements are not recognised, proprietary estoppel will lose contact with its roots and risk becoming unprincipled and therefore unpredictable, if it has not already become so. 
a claim for the imposition of a constructive trust in order to provide a remedy for a disappointed expectation engendered by a representation made in the context of incomplete contractual negotiations is, in my opinion, misconceived and cannot be sustained by reliance on unconscionable behaviour on the part of the representor.
But there is lots of juicy stuff in there. Well, juicy if you are an equity geek, and I am, on the side.