"Today is the Day" parts 1 and 2 are such a great insight into what could have become of TTSCC could have become had it not been given the classic "Fox Treatment", cancelled in it's prime before it can hit its apex.
No, this episode isn't jam packed with action, it's more story and character, a glimpse into Jessie's past and how it intertwines with both Derrek and Cameron.
The writers did a great job with exploring the idea of time travels effects on the past and the individuals storyline. Derek concludes that Jessie, well, isn't his Jessie, not from his future. She's not the girl he loved, for she would never be so cold and ruthless.
Very interesting and I highly recommend.