As much as respect Flash developers' opinions on whether or not widescreen should be available, I've found some games or movies where it simply wasn't absolutely necessary or was more of a conservative choice, rather than a decision based on the submissions ability to function or enlarge gracefully.

This script puts the power back in the user's hands and allows them to make mistakes while viewing the portal and to decide for themselves whether or not the flash runs properly on their particular computer in the wide mode. Now for the disclaimer:

The author has made his or her decision based on the experience on their computer. Your computer may not be powerful enough to run all submissions in widescreen or it may not run properly at all.

(Linky)