• Does "Messages in iCloud" work for syncing regular SMS messages too, or does it only include iMessages?
• It looks like there's no corresponding macOS update today to add Messages in iCloud support, is there? Should we expect it to be bundled into the next minor macOS patch, or is it more likely to be pushed into macOS 10.14?
It works for all messages, that is, SMS and iMessages. You turn it on in the iCloud account settings and it uploads everything. The device needs to be connected to mains power though. Otherwise it pauses the sync process until you do. The upload/download progress is shown at the bottom of the screen in the Messages app.
[0] http://www.iblacklist.com.br [1] https://tinyapps.org/blog/misc/201307210700_iphone_text_auto...
I'd also suggest sending feedback to Apple periodically at https://www.apple.com/feedback even if it seems like the feedback is never taken into account for changes or new features.