I just upgraded and the look is indeed different. There is an extra button “CHOOSE DEVICE” button (compared to v1.7.5) that asks you what Raspi you have. Hopefully they are using this info to avoid writing images that are not compatible with your Raspi and not just doing Raspin demographics.
As indicated above, Advanced Options is now called “OS Customization” and access to it is gain via the workflow driven by the new “Next” button (the " Enforce choice" mentioned above), where you are asked if you want to do customization.
The “OS Customization” has only a bit new (see above about the button to run SSH-KEYGEN) compared to the Advanced Options and the layout is nicer (IMO) with “General”, “Services” and “Options” tabs.
One thing I miss is the ability to default Advanced Options aka “OS Customization” to “this session only” or to “make permanent”. The new “equivalent” appears to be the “NO, CLEAR SETTINGS” button (see above). Seems to easy to wipe out customizations to me…
The “Write” button is gone ( ). Instead, clicking the “YES” or the “NO” button in the “Use OS customization?” dialog will provide the warning dialog originally found after clicking the Write button