After some thought, here's my ranking...
1. White Bear
2. Fifteen Million Merits
3. The National Anthem
4. The Entire History of You
5. Be Right Back
6. White Christmas
7. The Waldo Moment
"White Bear" and "Fifteen Million Merits" are unmitigated masterpieces, and I will return to them for years to come. The next four I loved. I'm sure my various affection levels for them will shift slightly upon rewatch, but they're all great.
It's probably best that we don't talk about "Waldo." But I guess I will, for a moment (with spoilers). It's sufficiently poignant and depressing, with a suitably painful ending, but it's still so profoundly ill-conceived. There's a moment when Jamie is embarrassed by Waldo's political rant and regrets not having been funny, but the problem is, Waldo was never funny at any point. To muddle things further, Jamie, and I think the script itself, acknowledge that Waldo is kind of dumb and terrible in general. So what's the point? This story has no idea where it's going. There are arcs and straight lines that lead nowhere and just kind of collide into sad mush.SEVERE SPOILERS for White Christmas
Really liked White Christmas...
I think I predicted the girl's suicide wish and the confession way earlier than I was supposed to. I rarely predict things like that... Either my Black Mirror sense was activated, or those twists were overly telegraphed. However, the Asian twist was absolutely brilliant and came out of nowhere for me.
There were a bunch of other fun little reveals, like the fact that John Hamm was omitting details of the botched date not really to hide them from his supposed co-worker, but because he was embarrassed to repeat them to the people in the room.
And then, in true Black Mirror fashion, in turns out that all tangents were 100% relevant and would come into play in delightful and surprising ways. If only more movies and TV shows cared as much.
I didn't buy that a "cookie" could replicate one's consciousness, for many reasons. I just kind of had to go with it.
As Garam said, the imagery of being blocked was probably the highlight of the episode. Reminds you just how visual this show is. The things that linger and haunt me from each episode tend to be visual.
I thought the plothole was the kid. I didn't get why she was unblocked when the ex died, but maybe I missed a bit of dialogue explaining it.
They say a block "extends to offspring." It extends the wife's block to her daughter, but doesn't duplicate it. So when that (single) block is nullified, so is the extension. It's software logic, which I absolutely buy in this universe.