First of all, I'd like to say that it really bothers me that someone who claims to be a native english speaker (not sure who made the comment originally) would argue that "are" is in valid grammatical usage in the "sentence" (footnote 1): "the list are now up to date" (IN ANY STATE OR COUNTRY for that matter). This is very disappointing to me, and all I can say about it is that I would recommend that any such person avoid writing and speaking as much as possible so as to not embarass himself.
If you are trying to make a statement as to the accuracy of the list, w.r.t. events over time, I would recommend a statement such as:
The list is current as of XX/XX/XXXX. (footnote 2)
The problem with a statement such as "The list is now up to date" is that it is inherently useless whether it is true or not. For instance, if the list IS up to date, then the statement is true, but at the same time, if the list is not up to date, it will still read that it IS until it is updated, at which time it will be up to date again. In other words, this statement provides no information, since when it's true, it's what you would expect, and when it's false, you don't have any incentive to change it to reflect the truth, because in doing so, you could just update the list and make it true again.
A last updated date at least improves this situation slightly by indicating how "stale" the list is. If, for instance, no changes have been made to the list for some time, but the list is believed to be up to date - nonetheless - then the maintainer can change the "last updated" date to reflect that the list has been checked for accuracy and completeness more recently than the last time it was changed.
(1) in quotes because in my opinion, something that is not grammatically correct cannot be called a sentence
(2) I'll admit I'm not sure of the grammatical validity of this statement, as the list was current, but is not necessarily still current, but I think "is" is the more customary usage here, than "was".
Kelly Leahy