xhtml 1.1 is the evolution of xhtml 1.0, right? So i wonder what are the main differences between them. I've been using xhtml 1.0 strict for a while but, if there's an evolution, i'd like to know if there's something better about it.
obs: there are several questions that LOOKS LIKE this one but most of them are about html vs. xhtml or transitional vs. strict. I hope you don't think this is some duplicate (if it is, i couldn't find it).
thank you.
Apart from the few language changes identified in @Francois's answer, the main difference is technical. XHTML 1.0 was defined partly as an intermediate step, as a way to allow web authors to move from HTML4 to the XHTML syntax.
XHTML 1.1 was a reformulation of the language into a series of modules as a framework for future development of the language by spec writers, allowing various parts to progress under separate editors and working groups, each able to progress at their own pace. You can see the same modularization process with CSS 3.
Whether modularization is a good or helpful thing or not is a matter of opinion, and there is some evidence that spec modularization doesn't work terribly well.
As it happens, with the next XHTML specification being developed as part of HTML5, that is being constructed largely as a single monolithic specification, with just a few satellite specs to augment it.