This certainly does leave a lot more to keep track of, but it's also rather reminiscent of Final Fantasy Tactics, which is always a good thing. That said, this would probably be easier to manage on an electronic game than a paper and pencil game, since the computer could keep track of all the rules and the like more quickly and efficiently than the DM and players. The pie wedge is an excellent idea for a visual model and would probably alleviate this problem.
[addendum: It might be a good idea to have a multi-tiered pie chart here. Basically, have a large circle divided into 6 wedges, then draw another circle or two inside. The wedges closest to the center represent the current round, the blocks just outside the next round, and so on. You could represent characters/effects with game pieces, extra miniatures, or just scrap pieces of paper with symbols or names drawn on them. Each time a round ends, scoot the pieces closer inside.]
ValhallaGH, I too thought that the card system of Deadlands was rather nice, but in my experience it's a lot easier to stack cards than cheat to roll high (ignoring the possibility of weighted dice). One of the other players in the one Deadlands campaign I was in knew how to stack cards, and he's the one that shuffled them each time. I believe my character managed to make a grand total of 3 actions in the 5 sessions we played, and the third player managed 2. This issue can be alleviated by the DM doing the shuffling, but there's still one issue. Due to the number of actions, most encounters won't last much longer than one round with a card system (or at least none of them did in the Deadlands campaign), meaning that one bad initiative roll can screw your character for the entire combat. A player with modestly bad luck, and/or with a low init character, can end up feeling rather left out while the rest of the party takes all of their actions and he's stuck holding the 5 of clubs.
[edit: I forgot to mention this when I first posted (or, rather, I had only taken a cursory look at the .rtf), but I have some confusion as to what needs to be done under certain situations. How do you resolve it when two characters are in the same segment (and if silmultaneous action occurs, how do you resolve this?)? Also, the .rtf implies that, when taking a full attack, the fighter has to wait several segments before he's able to get off his attacks. Personally, I'd have the full attack take place all immediately - it takes away a little from realism, but it prevents the target from cheating and taking a 5-foot step away to avoid the pummeling.
Also, I was curious about the weapon delay. Does it only come into effect when the weapon is used, or is it always in effect? For example, take a rogue with a dagger and a fighter with a greatsword. Obviously, if they both attack in the same segment, the rogue will go again 3 segments before the fighter. If, however, they each take a half-move in the same segment, would they both be able to take another action the next segment, or would the fighter have to wait 3 segments longer? If it's the latter case, this seems to unbalance things greatly in favor of the characters using light weapons.]