I don't think I'm alone in thinking that the XPages hijacking of the id-attribute on fields/etc is a bad design choice. Matt White is amongst the people that have struggled with/found a way to work around the problem.
I don't think there has been much public debate around the problem. Hopefully enough people will read this post, to get a debate started, and maybe get IBM to change it's implementation in the nearby future.
With Dojo as the base framework, there is no reason for IBM to use the ID-attribute to reference elements. There is a speedy CSS selector engine available to them that enables them to use any attribute they want to, to get a pointer to an element. There is also a CSS selector API in the works, which when implemented (soon, in FF 3.1, others will follow) will allow even faster lookups.
In the still not finished HTML 5 specification by W3C/WHATWG, a data-attribute is proposed to use for storing custom values in. Since XPages is something that will last for a good while, and IBM want to play with the cool kids and follow web standards. Why not use data-attributes to add pointers for the XPages engine, and leave the id-attribute to us developers?