Help me tidy up my widget code

Your Class Name:

1. I’d prefix the class name to make collisions less likely– something
   like Your_Initials_Today_Video, or namespace it, but be aware
   that PHP namespacing requires a higher versions of PHP than
   WordPress requires. That could cause issues.

Your Constructor:

1. You can use __construct instead of Today_video for your
   constructor. WordPress no longer supports PHP 4, so you shouldn’t
   have to either.

In your widget function:

1. $instance should always be set. You don’t need to check for it
   explicitly, and even if not set isset( $instance[ 'title' ] )
   would still operate correctly and without error. That “wrapper”
   conditional is unnecessary.

In your form function:

1. Embedding that markup in the template argument is going to be
   prone to markup error. I would add a set of individual parameters–
   height, width, src, whatever you need– and generate the
   iframe dynamically.

While I might do a few things differently, I wouldn’t call the code “messy” and I didn’t spot any major issues, nor does it trigger any warning or notices.