Q:What database changes are there for contributions in 3.0?
Quite a bit is new, but most of it will upgrade from your backup file automatically.  DVD Profiler 3.0 uses the full UPC/EAN, and validates additions when they are made.  Your existing database will be converted, and UPCs/EANs will be updated to the full code during the restore.  For some profiles, you may need to adjust the UPC by selecting DVD->Change UPC.  For your convenience, DVD Profiler will create a flag set for the profiles it was unable to update automatically.

DVD Profiler also uses the full DirectX disc ID (globally unique), instead of the disc format ID (not unique) for profiles added by disc ID.  If the profile has existing disc information which includes a DirectX ID, the profile ID will convert automatically.  If not, you'll need to insert the disc into your DVD-ROM drive to re-read the ID in order to contribute that profile.

Audio tracks have seen a complete overhaul, and should be far more straightforward, and result in more accurate entries.

Cast and crew may now be listed multiple times, and both cast and crew sections now contain "Dividers" which can break the listing up (for instance by episode).  Cast and crew both contain "Credited As" entries, and both support optional "Birth Year" fields.  With these changes, full accurate credit information will no longer result in a disjointed database.  "Voice" and "Uncredited" checkboxes round out the cast improvements.

New fields for the profile include "Country of Origin", "Media Type", and "Original Title".  In addition, some field length limits have been raised, including a new 100 character limit for the "Title", "Original Title", and "Sort Title" fields.

There are also new language types and a trio of new features to track - Interviews, Outtakes/Bloopers, and Storyboard Comparisons.

Q:What other changes are there for contributions in 3.0?
The biggest change is the new requirement for a paid registration in order to participate in the contribution system (submitting and voting).  Although a paid registration is no guarantee of a higher quality of submission, it does allow us to effectively prevent fraud.

The next biggest change is the switch to daily database updates.  At midnight, US Central time, the database updates will release automatically.  Additionally, the 2-day waiting period no longer applies to new profiles, only changed profiles.  During the first week of launch, we expect to generate intraday updates as well.

Contributions including cover scans that update existing scans will now present the old and new images to the submitter side-by-side.

Contributions for brand new profiles are now 1-click, and no web page is presented to the contributor.

The rules have been updated in minor ways to match the new data structures.  Further updates will come, but nothing earth-shattering is planned.