Hi Zarak,
You can certainly try it; it may just work, unless the local cable system shifts its HD channel allocations, in which case you'd need the outboard box or a cable card set.
It used to be the FCC required cable operators to supply the basic network signals, albeit in standard definition if you simply connected the cable with no box. I don't know if that has changed.
CableCard was intended to be the great upcoming technology that would get rid of the rental outboard box, but there were problems initially and it never really caught on. Or maybe it was the cable lobby and all those nice cable-box monthly rental fees (likely the latter. . .)
And I agree with you opting for a plasma--no color shift or loss of contrast with off-angle viewing. The Panasonic plasmas I've looked at are excellent.
Regards,
Alan
