The only new (mid-priced) S is the S470B with the happy colors (Sky Blue, Red and White), just recently released in Japan and up for release in at least the EU for
2009 since it's already listed at thomann.
No news about the S320. It's still in production, so it probably returns unchanged. Anything cheaper than that and you'll end up with a S with an Edge III (which doesn't exist).
I'm still wondering if they going to discontinue the SA series in favor of (lower priced) SV models. Probably not since the flat back SA body is cheaper to produce and because of that more suitable for 100 and 200 series guitars, but you'll never know.
More new cheaper guitars: a Black GRG250DX with red pickguard, binding and teeth, Non-Prestige RGA's and Artists and the new Darkstone guitars.