While 30 Years of Wrestlemania doesn't splice in actual commentary like The Attitude Era mode did (although actually hearing Savage's voice over his in-game character was pretty cool), I did notice that they use audio from the actual matches. I was smiling when I could hear Andre's grunt as he headbutted the post at WM 3. Also, if you happen to glance at the video board during the Steamboat/Savage match, it looks like real video that you're playing. Amazing.
On a side note, I love it when 3MB's music plays during the opening screen with The Rock. It's an inadvertently funny mash-up.