If it was, no one has made anyone mention of it on the commentaries that I've heard so far. Although on the commentary of the S4 prequel, Jon Cassar says that that was shot on HD video so maybe they did end up using HD for the entire year as well.
I think the pictures of characters on the box, discs, and booklet are worse spoilers than the menus (at least the nine episodes I've seen so far). Although there was definitely one menu that made me think "I'm glad I've seen this episode."
I've been listening to the commentaries as I get to them and surprisingly the Shannon Doherty and Evan Katz is probably the best one I've heard so far. Doherty actually asks some interesting questions and gets Evan Katz talking about some different stuff than people normally talk about on other 24 commentaries. I figured that Doherty would only say things like "Wow!" or "Oh my god, that's so exciting!" but that's not the case. Sorry, Brenda.
Yeah, Mat is right. Apparently, she was just visiting the set and they invited her to be on the commentary too. She does joke that she wants to an extra in the CTU just so people see her and say "Was that Shannon Doherty?"
The writers never knew what to do with the character so they figured they'd write her off when they got rid of the rest of the cast. She said that she wants to concentarte on her movie career too.
The sad thing is that when Elisha Cuthbert was given good material she was good in it (like the wonderful scene between her and Jack when he's flying the plane with the nuclear bomb in S2) but unfortunately those really good scenes for her were few and far between.