You can do a sunlight 1 1 1, sunlightpitch 90 to make the skylight look like the old behavior (casts light in all directions) as a workaround for the way it is now.
Unless it gets independent from the sunlight in the future, that is.
Anyway, @mrmister, about the performance problems we could have, most (if not all) official maps are running pretty good as it is, on my machine (gtx 650 ti, phenom II x4 965, mid-range ish :p ), even without optimized versions.
Unless you Spawn a good chunk of bots (20+), then things start to get dirty .
This release is still far from done, but so far, so good ^^.
Ex Iron fist level designer/ Ex Revelade Revolution level designer, 3d/2d artist, and still trying to figure out sound design...