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Xfce4-panel 4.10 Roadmap
That are a bunch of (mostly small) feature requests in bugzilla under the 4.10 milestone. Just some highlights here.
A plugin that can contain other plugins so it is possible (if you want to put time in this) layout plugin in, for example, the opposite orientation, multiple launchers in a grid, other sizes and things like that.
Merge actions and session plugin
There are a couple of plugins in Xfce that handle the session. The panel has the actions plugin, xfce4-session the xfsm-logout-plugin and there is the xfswitch-plugin. Since this is all very generic, it makes sense to put this in a single plugin to avoid confusion for users.