I like the announced specs for the iMac Pro, but I’m waiting for Apple to unveil a large external display. I have a 27″ 5K display and I want more space for photos and UI designs without having to deal with multiple displays. Check out Dell’s 32″ 8K display. According to Sven Neuhaus’ PPI calculator, the Dell’s PPI is about 280, which is not ideal for macOS. To fit 8K of pixels at the 220 PPI that makes for comfortable rendering of the macOS interface, Apple would need to build a 40″ diagonal panel. Sounds good to me.
The other thing I’m really looking forward to is APFS in High Sierra. I had to reformat an external drive recently because of corruption that likely could have been avoided with a modern filesystem.