WordPress.org

Will my identicon be the same on different blogs?

Yes, if they're using the standard version (and I didn't mess up anything).

Can it generate Identicons only for people without gravatars?

Yes. Just turn on the Gravatar option in the Identicons options page.

Can I add Identicons to the Recent Comments Widget in my sidebar?

Yes, this plugin provides a replacement widget to Recent Comments (since the default widget doesn't provide the commenter's email).

Does it work with WP 2.5+ themes with builtin avatars?

Yes, just select the WP 2.5+ Theme option to the Automatically Add Identicons setting in the Identicon control panel.

Why should I use this plugin when Gravatars now has Identicons?

The gravatar identicons are pretty good but if you want more control (custom colors, transparent backgrounds, different numbers of blocks) or just want one set of avatars for everyone on your site, then this plugin's for you. Otherwise, sure go with gravatars (just set &default=identicon in the gravatar url).

Could you implement XXXX feature?

Probably (if I have time/know how). It's definitely worth a shot since I'm always looking for feedback on how to improve my plugins.