It turns out that the iOS 7 upgrade has indeed broken a critical function of wineCellar. The fields which, when edited, use a field with a “picker wheel” are missing the field. This means you cannot tap the field to add new values which are not already on the picker wheel.
The issue has been fixed and version 1.18 has been submitted to the Apple Store for review. A side benefit of 1.18 is it was built with the iOS 7 libraries so it takes on the new look-and-feel of iOS 7 when running on upgraded devices.
For an explanation as to why this was not caught ahead of time, see Doug’s blog.