1 - What should we expect for update/converting experience 1.9.1 to 2.0?

We're doing our best to make this process as painless as possible. Any parameters that have changed we've made sure to migrate correctly in our installer. However, there are many API changes that could affect various plugins. As a result of this CB 1.x plugins are marked incompatible. They'll still run, but may not be entirely functional. CB 1.x plugins also can not install on CB 2.x. We're working on improving our legacy compatibility right now as well to make backwards compatibility even better.

2 - What 1.9.1 extensions/plugins will be a challenge for conversion?

All of them. They will all be upgraded after CB 2.0 has released. Most will receive a quick minor bug fix release to first address compatibility issues followed by new major releases.

3 - Is there an ETA for 2.0 general availability? Are we talking weeks, months or quarters? General notion of what to expect would be appreciated. Fully understand the issues with ensuring quality and stability are prime.

When it's done. We're not providing a release date as we're trying to ensure everything is done properly before going stable. We are however feature locked and should not be seeing any further features being added except what's already on our list found below unless we find it absolutely necessary to add.

forge.joomlapolis.com/projects/cb/issues?query_id=51