Here are some difference between Weblogic DEVELOPMENT Mode and Production Mode:
Development Mode:
1) The default JDK for development domain is Sun Hotspot
2) You can use the demo CERTIFICATES for SSL
3) Auto deployment is enabled
4) Server INSTANCES rotate their log files on startup
5) Admin Server uses an automatically CREATED boot.properties during startup
6) The default MAXIMUM capacity for JDBC Datasource is 15
Production Mode:
1) The default JDK for production domain is JRockit
2) If you use the demo certificates for SSL a warning is displayed
3) Auto deployment is disabled
4) Server instances rotate their log files when it reaches 5MB
5) Admin Server prompts for username and password during startup
6) The default maximum capacity for JDBC Datasource is 25

Here are some difference between Weblogic Development Mode and Production Mode:
Development Mode:
1) The default JDK for development domain is Sun Hotspot
2) You can use the demo certificates for SSL
3) Auto deployment is enabled
4) Server instances rotate their log files on startup
5) Admin Server uses an automatically created boot.properties during startup
6) The default maximum capacity for JDBC Datasource is 15
Production Mode:
1) The default JDK for production domain is JRockit
2) If you use the demo certificates for SSL a warning is displayed
3) Auto deployment is disabled
4) Server instances rotate their log files when it reaches 5MB
5) Admin Server prompts for username and password during startup
6) The default maximum capacity for JDBC Datasource is 25