There are some common problems people run into when using Tastypie for the first time. Some of the common problems and things to try appear below.
This is actually not a bug and JSON support is present in your Resource. This issue is that Tastypie respects the Accept header your browser sends. Most browsers send something like:
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Note that application/xml comes first, which is a format that Tastypie handles by default, hence why you receive XML.
If you use curl from the command line, you should receive JSON by default:
curl http://localhost:8000/api/v1/
If you want JSON in the browser, simply append ?format=json to your URL. Tastypie always respects this override first, before it falls back to the Accept header.