[wp-hackers] wp_magic_quotes makes me sad panda

[Mike Schinkel]

On Sep 28, 2010, at 6:14 PM, Otto wrote:
> Older plugins that relied on magic quotes may suddenly break if WP
> starts returning non-MQ values. This could open security issues.
> 
> Maybe they'll eliminate magic quotes in WP 4.0. And only allow plugins
> that declare themselves 4.0 compatible to be loaded. ;)

That brings up a question.  What are the strategies within WordPress and/or best practices by plugin authors to enable deprecation of features so that core can transition over time?

For example, here's a ticket on the admin menu system and we are working on ensuring 100% backward compatibility:

http://core.trac.wordpress.org/ticket/12718

However,the array structures used by WordPress for the admin menu system are obtuse at best and could benefit from a forklift upgrade at some point done the line, maybe 3.5 or 4.0?  Are there any strategies where we can enable this kind of evolution?  Maybe something that continues to support "the old way" but disables new features for users that continue to use plugins that don't support the newer features.  Maybe a "plugin_supports()" functionality and best practices for using them?

-Mike