One thing I'm wondering is if photographs taken by Sims will transfer through the gallery. I started a thread in the GTW part of the forum and once person replied that we can (it was the only reply I got so not a great sample size :p), but I'm interested to see if it really works. I know paintings do transfer now, but the images on those are technically in everyone's game files, while pictures are completely custom. I have to wait 6 hours before GTW unlocks over here, but it would definitely be worth a test.
I did make my simself pump out paintings for future decoration since the latest patch and I noticed I was already able to paint from reference, despite not having the expansion pack yet. She took a picture with her phone and made a painting of it. If those paintings and pictures survive the upload and download progress, then we'll have a lot more wall decorations available :#