Lightroom 4.1 final is now out, with support for the Fuji X-Pro1, so we can expect a final version of ACR with X-Pro1 support very soon as well. (For those that don't know, ACR and Lightroom share a common raw conversion engine, and releases track closely.)
Sadly, the Lightroom final release shows exactly the same chroma smearing as the ACR beta. A crop of the comparable area shown in the original posts is below.
BTW, Lightroom does an excellent job in many other respects - the diagonal edges of the paperclips are just amazingly clean - I very much doubt that any other raw converter could match them. But the chroma is a mess!!
Turns out that X-Trans sensor really wasn't a good idea.
Updated 7 June 2012 - also see this post
Lightroom 4.1 final, Fuji X-Pro1