I read the Ars XOOM review, and I'm not worried in the slightest. Android has a history of fast releases to market, and generally good bug-fixing and general improvement. I suspect that these concerns will disappear in short time. Homescreen replacements, new widgets, and new applications will improve the users experience greatly.

I also suspect the Xoom as being incomplete relative to Motorola, and may not be the same with other vendors (eg. Samsung). Time will tell.

Android has been moving towards the quick update model found in Chrome noted in the separation of OS from applications, as well as some system facilities (eg. UI fragments lib). I expect android to move forward at maximum speed with numerous innovations.

I foresee Android tablets being as successful in that arena as Android handsets were in theirs.