These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Also, the captains and hosts were acceptable targets, for being fat (Phill), bizarre (Bill), from Swindon (Mark), completely insane (Noel) or Irish/tactiturn (Sean).
Adorkable: Many guests over the course of the series, but Mark Ronson clearly stands out.
Broken Base: As of series 25, fandom can't decide whether there's new life in the show with the latest reboot or if it's time to let it die. Some fans started thinking this when Mark Lamarr left. And again when Bill Bailey left.
The host issue: Some fans want Lamarr back. Others want Amstell back. Others don't care who, they just think the show is funnier with a permanent host — an answer may have come in the form of Rhod Gilbert.
Crosses the Line Twice: A lot of the jokes from the series can fall under this. Series 14, Episode 3 had Mark, the team captains and some of the guests doing some "Nazi japery". It goes several steps past potentially-offensive to downright hilarious.
Mark Lamarr: "This is the greatest punchline of all time!"
Ear Worm: "Moby, Moby, Moby, Moby, Michael Stipe..."
Ensemble Darkhorse: Athelston Williams aka "Number Three", a catatonic-looking black man who achieved Memetic Mutation after memorably appearing in the identity lineup, and then became a recurring figure. Seriously, he was busy one week and they got a stand-in.
There are quite a few celebrity guests, like Donny Tourette, Dappy and Preston, remembered more for their NMTB appearances than anything else they've done in their careers.
"Funny Aneurysm" Moment: Following Amy Winehouse's death at 27, her appearance in series 19 episode 4 has become this.
In the same vein, Mark Ronson's appearance wasn't much better, given how about a third of the jokes were about Amy dying in a ditch.
In the '99 Christmas Episode, one of the lineups was a bunch of cardboard cut-outs of rappers, with the question being who hadn't been shot. The team (Phill's) was given a toy gun to shoot at who they thought the answer was ("so he feels like a success"). To make things even worse, among the line-up was The Notorious B.I.G. and Tupac Shakur. Again, this was in 1999.
Simon (to Amy Winehouse): You want us just to sit here while you drink yourself to death?
Hilarious in Hindsight: When Simon was a guest years before he became host, Mark jokingly accused him of "stealing his act" and Simon referred to Mark as "daddy".
When Noel Fielding first went on the show as a guest, he commented that the intros round was his favourite bit of the show. Not too long later, when he's captaining, which round can he never bring himself to do properly?
In series 14 episode 7, Phil's team performed the intros of "Special Brew" by Bad Manners, and "I've Got A Combine Harvester..." by The Wurzels. Guess which bands performed the intros in the series 15 episode 7, for a Christmas special...
Also, Phill and Simon. Also also, Simon and Stephen Fry, to the extent that Phill at one point called Stephen Simon's "boyfriend", and Simon asked Phill not to "mock [their] intellectual Greek love". All in jest, of course.
Simon introducing Matt Baker as, 'saucy ex-Blue Peter stunner.' A bit gratuitous, no?
Then again, Simon quite often introduces the guests in a complimentary fashion, like when he called Fyfe Dangerfield 'all round lovely man', or Midge Ure 'sexy eighties hottie'.
Phill: "Roy Wood just mounted me! I didn't think that when I got up this morning — 'Today I think I'll impersonate the Smiths whilst being mounted by a glam legend!'"
Phill bending over and lets James Blunt mount and spank him.
Oh, let's not forget the episode in which Danny Dyer was a guest, and proceeded to call Simon 'babe' every time he directly addressed him, provoking much giggling and coquettishness on the part of Simon.
Averted in this exchange between Donny Tourette and Simon:
Donny: The only reason I'm on the show is 'cause you told everyone you fancied me, dude!
Simon: It's not, it's 'cause we have difficulty booking people!
There's a beautiful moment of this in Season 2 between Brian Molko and Bruce Dickinson, greatly helped by the fact that Brian could easily be passed off as a beautiful, young Iron Maiden groupie.
Bruce: You're too young to remember this band. Go on, stick your thumb in your mouth.
Brian:(Obliges) Anything else you'd like me to stick in my mouth, while we're at it?
And in that same episode, Brian cuddling up to Phil after the former made a jab at the latter's weight.
Simon towards Danny from Mcfly. He had previously stated that Danny was his favourite member of Mcfly and then, when he was on the show, introduced him as a 'hunk', kept showing a picture of him performing naked, and acted like a spurned lover because they lost contact after their interview on Popworld.
The episode wherein Simon and Phil mime 'No Air' in the absence of Bill Bailey kind of reeks of OT3invoked
And in the same episode, Mark Ronson giving Tim Minchin a lap dance.
On his first ever appearance, Noel Fielding demonstrates spooning on Bill Bailey, who then commented how nice it was.
Oddly enough, between Simon and the Preston stand-in:
Amstell also did this in the first episode he hosted, saying that with a new opening and a new host, there could be only one possible outcome: "Welcome to the last series of Never Mind the Buzzcocks!" This was also a reference to just that happening to They Think It's All Over when Lee Mack took over as host.
David Tennant:Mc Fly's song contained the lyrics "there's nothing on Earth that could save us since I fell in love with Uranus." Which as it happens was a line removed from the pilot episode of Torchwood. Barrowman!!(shakes fist at camera)
Mondegreen: The point of the "Indecipherable Lyrics" game is for the teams to come up with amusing lyrics for songs whose words are hard to discern.
WTH Booking Agency: Some of the choices of guest host post-Amstell are attracting this criticism (particularly David Hasselhoff).