I've always run Winterboard in the past jailbreaks but this time around (4.1) decided not too just to see if my iPhone runs a bit smoother with less hassles.
It does. I'm a convert. No more Winterboard for me. Sadly though as I don't know how to put themes on the iPhone without using it I have nothing to show off.
I simply change out my wallpaper every now and then and use 'Shrink' to adjust the size downward of my icons a bit (80%).
It's good enough for me. Really, unless the theme is spectacular nothing really fascinates me to a point I'd want to ever add Winterboard again.