According to Trace Urdan, in the latest Education Signals...

Sakai adoption is not meaningfully hampered by usability issues, but by obstacles to the risk/rewards of an open source solution to begin with. Wider Sakai adoption, we think, is more likely to come about by increased activity among its commercial supporters than by tweaks to the platform itself.

Trace and team are reacting to Michael Feldstein's post from September...

I'm so close to the software as a user that I place a lot of importance on improving the user experience. As a member of the Sakai community, I see this as a very important priority for our collective energy. So much so, that I have donated some time and energy recruiting others willing to contribute to the improvement initiative, and I've committed some funding for it.

At the same time, I agree wholeheartedly with Trace. I speak with a lot of people about adopting Sakai, Kuali, and open source in general and perceived lack of support is the #1 concern.

It's not surprising that Actuate's 2007 survey of enterprise adoption of open source points to this perception as a key barrier to open source adoption. I just downloaded the full report but found Matt Asay's summary helpful this morning and I plan on digging into the rest of the report soon.