While testing the fix for the default values problem on the latest dev release I noticed this one:

When a user (with non-admin permissions) creates a poll, there are 2 choices by default. If you click the more choices button, 2 fields are added to the form - the 3rd choice text field and the starting vote count for that choice (the starting vote count field is not visible for choices 1 and 2). If you save and go back to edit the node, the starting vote count field no longer appears with the 3rd choice, so it looks like the permission is not properly checked only when you click "more choices".