Just flew USA-CPH on a discount economy (W) ticket with an optiontown upgrade to C and only received 25% points.
I've gotten points for the upgraded class the two other times I've successfully used optiontown, so I guess this is new from 1 august. I'd be curious to know whether other people have seen this for very recent flights.
I didn't try upgrade the outbound (it was already booked in Q so 100% points and I figured the flight would be overbooked anyhow). It was an open-jaw ticket, purchased on travelocity rather than SK website, though I don't see that this would matter.
For me, this pretty much makes optiontown useless, since I'd rather spend the money on making sure of 100% points than on getting the upgrade+25% points.