The Oracle Dev Gym is still in an "early adaptor" state; you can take quizzes, including our weekly competitive quizzes, there. You can set up workouts and so forth. But we are not yet offering it as a day-by-day alternative to the "traditional" PL/SQL Challenge.
Here's a quick update:
1. The URL devgym.oracle.com is now configured, so you can more easily go directly to the Oracle Dev Gym (instead of going "through" the PL/SQL Challenge.
2. We've come up with a simpler, more immediate design for our home page. Rather than having to choose "Take a Quiz" from the home page, and then go through another layer of selection from there, the home page now offers immediate access to quizzes.
The previous home page:
The new home page:
To take a competitive, weekly quiz, click on Tournaments.
Please give it a try and let us know what you think.