A very interesting and surprising episode. Derek's case was truly one in a million and even though this is Grey's, there was still a chance of failure. Lexie's diaper monologue was wonderful and I'm glad how she and Cristina seem to be getting closer. There were some great Callie/Arizona and Mark/Lexie moments in this episode, i.e. holding hands (Callie/Arizona) and the "You love me" line (Mark/ Lexie).
Alex was really emotional in this episode and I felt really sorry for him, even though he acted like an ass in some moments. Reed is starting to grow on me, but I'm not liking Jacskon so much after this one.
I hope Izze and Mer get back and that we have more episodes like this.