I think it depends. If everyone just gets a check, then absolutely no question taxable.
BUT....
If each account with your shares is credited with cash, example: your IRA has FMCC shares, so that account is credited money in a MM fund linked to it (all brokerage and IRA, Roth accounts, etc usually have an MM fund attached). So if money goes to your IRA account, then not taxable until you withdraw,casual rules apply. If credited to a ROTH? That's where it would get interesting! and pain the government to all hell. It would mean that money can't be taxed at all! Based on ROTH rules, of course. So if you did as Guido was doing, and got the majority of your holdings in a Roth, that could be a sweet pay day.
I have shares in an IRA, Roth and a regular brokerage account. So I'd have a mixed bag of tax circumstances.
It says in class action literature that I've read that a payout is not necessarily in cash, that many opt to give shares or fund accounts.
Stay tuned