I currently have an Omega subtheme located as a subdirectory of the .../sites/all/themes/omega. I think this location was a requirement for Drupal 6. Now that we're on Drupal 7, I'm looking for the best practice on where this subtheme should be located. Does it make sense to add it to .../sites/all/modules/custom/ or maybe create a new directory like .../sites/all/modules/themes/.

Any best practice advice would be great.

Thanks