Refactoring subscriptions (make them plugable), porting to D6

First, thanks a lot for the subscriptions module. I've used it successfully for a long time.

The Drupal 6 will be released very soon. Is there any plans on migrating the module to D6 and estimates when it can be done?

As the subscription module is getting bigger and bigger, I would suggest splitting it into several peaces - one would be the core API peace, others would handle different subscriptions - separate one for categories, content types, feeds, etc. Splitting the core API from the would allow easily adding other type of subscriptions as a separate plugins, for instance one for organic groups, as discussed here http://drupal.org/node/212248 without change of the existing code.

It also would be good considering e-mail as only one type of possible subscriptions transports. SMS gateway http://drupal.org/project/smsgateway for example can be considered as other subscriptions transport, xmpp bot might also work as a transport as well. Separating core subscription features from the transport layer would allow much easier support for other transports, and the users could select which transport they want to use.

If you would agree with the proposed roadmap, I could spend some time on migrating code to D6/refactoring the module.