I definitely think they should be banned.
Especially the item 'sets' that give you a massive bonus (+25 HP for scouts for example) just for wearing a hat.
There just has not been enough time for players to:
A: Acquire them (I'm still missing the scout pistol, and I play/trade fairly regularly)
B: Test them (No-one knows yet which combos give too big of an advantage)
Also remember that there were new mellees for both the Medic and Heavy, and while they seem fairly balanced, should also be banned in the interest of fairness
ALSO, priorax, that post on the SPUF is priceless. Why does the average TF2 player have a negative IQ? Some of the things they said were hilarious:
"At a guess, I'd say the lack of random crits makes it very hard to take down a wrangled sentry."
"Engineers are banned in comp. because they think it's skill less, like all the other class except Soldier, Scouts, Demomen, Medic and Snipers.
They're stupid."
"Basically if it can't easily be spammed out of existence..competitive players don't like it.
Because ya know..the more you spam the more professional you are."
"Spy stab and sap.
Sniper headshots Engi, team moves up and destroys sentry.
But oh well, most competetive players don't think out of their box"