don't get me wrong - I love grey's. but I'd rather watch a good written end than see my favorite show die the slow way or even get cancelled with an unsatisfying end (remember e.g. gilmore girls!?!). and after all we got what we want: Merder happily ever after!
and what do you expect to happen the next season? At least the focus would have to be switched form meredith to lexy - or they have to change the name ;-) but I believe that grey's is so awesome because of this team, and I wouldn't want it to become a new ER-kind of series.