Boeing recently published an excellant article on overweight landings in aero magazine. Its in 3rd quarter for this year. Its available online. Well worth a read.
In summary it says it should present no great problems. Certainly if you are in a twin its clearcut, lose 1 engine and you land ASAP. Overweight if necessary. ETOPS or no it doesn't matter, do not expose yourself your crew and your pax to more risk than necessary. This is justified as any degradation to the other engine will compromise safety of flight so you do not want to delay unecessarily before landing and dumping fuel would be an unecessary delay.
In a tri or 4jet then its a different story as losing 1 engine may not place you in a situation were the loss of a further engine would compromise safety of flight so there is more judgement involved. E.G. BA continueing trans atlantic on 3 engines having lost one on departure.
Anyway thats my take on things. Do read the article thoguh as its written by those much more knowledgable than me and has all the technical and legal detail involved.