After giving myself almost a solid week to cool off, I decided to try the combat changes with a fresh eye. I'm not sure if swing speeds have been adjusted a bit from the last time I tried them (this is what I suspect), or if taking a break from the game and playing much slower paced MMOs like WoW and LoTRO for a week gave me a different perspective. In any case they don't seem so bad to me now.
After spending an entire evening with the system, I can describe it more thoroughly. The current attack pattern is that your guy does a three hit combo, with a slight (maybe one to two seconds) pause where he leans forward holding his sword out in between combos. I have read that you gain more attacks in your combo chain as your base attack bonus increases but I can't confirm it (mine is at +1 on a level two wizard). I also haven't rolled up a new wizard just to see if his attack combo is fewer hits.
Overall attack speed is slower than it was before (at least at the low levels that matter to new players like me). The transition from the old system to this new one was absolutely jarring, and I'm still not convinced that it was warranted. Assuming for the sake of argument that the change was warranted, the way that Turbine handled the transition was horrible. We all wake up one morning and find that the combat has been greatly altered, without any real warning from Turbine that it was coming.
That said, I think the combat system in DDO is still overall quite good. Once I gave myself enough distance to see it with fresh eyes, I find that I am still having a lot of fun in DDO. Spells and special abilities are still as responsive as they have ever been. After adjusting to the pauses in between swing combos, the combat even begins to feel a little more rhythmic and strategic than it did before.
Edit: After more testing, the difference between what I remembered from last week and the way the game is playing now is actually lag. The patch originally added lag for me in places I wasn't getting any before. The crazy thing is that the lag affected mainly my swing animations, not walking around or other animations. In the last week lag has apparently been improved immensely. Tonight, it took me a while to stumble on a spot that was still laggy enough for the bugged animation to show up again. In those spots my dude now appears to swing exactly as I remember, holding the sword for a good long while behind his head before he decides to swing. Now that I am seeing the real swing speed nerf, I can see that I overreacted. If you give it a chance it's not that bad.