Revisions system

Will, can you please describe your content type exactly (fields and settings) and tell us which modules are enabled? Also, did you create your content type from the UI, or in code in a module?

Revisions seem to work quite well for me.

Revisions tested on custom content type with different custom fields, working properly (drupal 7 alpha 6)

Can you reproduce the bug yourself, if yes can you provide the exact steps

Closing this for now because it cannot be reproduced and the OP is not responding. Please reopen if necessary.

I'm experiencing this problem on a site I'm working on. It's a site that was built using OpenPublic with core Drupal 7.8. When I edit a node and try to view revisions, every revision link that I click on shows me the current version. This happens with every field that I've tried except the node title, where revisioning does seem to work as expected. However, it doesn't work with the body field or a taxonomy field that I tried.

The website also has the diff module enabled, but attempting diffs between versions shows "No visible changes" unless there is a change to the title. On the theory that the diff module might be the problem, I disabled it, but the bug persisted.

Could we get steps to reproduce from a clean install of 8.x or 7.x core?

Tagging.

I believe OP is about Diff module. 7.x-3.x supports fields, so that should solve your issue.