Recently I received an email from Chrome Web Store that they are ending support for manifest version 1 in favor of version 2. V1 extensions will no longer be indexed in the store as of June and they will no longer run in Chrome by the end of this year. I think this is a good idea as many of the older or abandoned extensions will be swept away making room for newer ones.
There are some significant differences between the two manifest versions. So if you have any older extensions, published or not, it's a good time to get busy and make the updates to stay current with version 2. Mine are updated already.