How to render links to youtube as video
I guess the simplest solution would be a normal textfield with a youtube-specific formatter. A formatter is some code that takes the value of a certain field and uses it to generate a chunk of html, displaying the field on your page the way you want. The downside of this solution is that it will add a separate field to your form.

A quick search found two sandboxes with youtube field formatters:


https://drupal.org/sandbox/Hydra/1404188
https://drupal.org/sandbox/double/1795842


Unfortunately I could't find an oficially released, stable module.

If you want complete control over your formatter, here's a tutorial how to create your own: Creating Custom Formatters with the Field API . In the comments, some commenters even say it helped them create a youtube field formatter.

[Update]

I just noticed the Googtube module, it seems to be exactly what you're looking for: like Video Filter module, but parsing regular YouTube URL's as embedded video's.