All in all, I loved it, especially:
* The jaw-dropping surprise ... though it was expected judging from its previous scene. Too Monica and Chandler in my book.
* The opening scene - love their wit and Sheldon's fitting (by mere serendipity) remarks, which are funny because they're true.
* The way Penny's each time more merged with the group ... in more ways than one. You can tell how close they are to each other.
* It was pretty much an ensemble - they all got screentime and appropriate storylines, and wonderful interaction.
* Nice to see how much Leonard had to put up with, sometimes you take those things for granted ... oops, I just started wondering what Saw trap would Sheldon be put in ... but I digress...
But there are some things I didn't like, TBH (which aren't sufficient to give the episode less than its well-deserved ten, though), such as:
* Amy being reduced to a laptop character, just like Raj's parents. It's getting old.
* 'Heard but not seen' stopped being funny since Maris (Frasier), to say the least.
* Why doesn't Howard simply GET a PhD? He can make enough time and he can surely pay its tuition - what sort of expenses does a man who lives with his mum have?