[TELECOM Digest Editor's Note: What may be a bit more tricky, IMO is
> when the purported message is to 'wish happy holidays' as our
> original writer noted. When such a message is conveyed, is it still
> in fact a 'sales call' or an advertising pitch? PAT]
If the intent is to drum up business, then most definitely, whether it says "Come and buy something" or "Happy holidays" or "Boola boola!" A very basic principle of law is that intent and foreseeable effect are of paramount importance.
There are also some laws against autodialing some kinds of numbers (hospital rooms, etc.) regardless of the purpose.