There is a lot of discussion on this board about the future of the Interface for LotRO, including numerous posts by
Frosty and
agentfive, two of Turbine's UI team. I could link you to all the specific threads and posts, but that would be an incredibly long list. Your best bet is to look through the forums here, specifically here in the Developer Discussions section of the board. Keep an eye out for the posts by Frosty and agentfive.
There is also quite a bit of information about how to work with what is currently possible here in the Dev Discussions sections, as well.