Ignoring the resource issues, MIST looks cool. For a long time my own personal nirvana has been a web-aware package manager than can query the various repositories and tell you what's new and what's changed. This way you could just click "Install" instead of having to wget/untar/install or copy/paste URLs into the package manager web UI (the way it used to work before arsdigita.com went offline). Perhaps this is the up2date to MIST's apt-get.
In a world of limited resources, however, I agree with Jun. My money would be on making OACS easier to install.
Regarding new-portal. Up to this point I haven't participated in the discussion. Clearly this is something of a pandora's box. Politics aside, it seems like there is room here for good-natured technical debate. On the one hand, there is a big advantage to using new-portal for admin pages. Namely, you get nifty auto-generated admin pages that expand as new packages are added to your system. dotLRN showed us that this is possible not to mention very cool. But the downside, as Ben points out, is that it adds yet another required package to OACS and generally raises the bar for writing new packages. To me this seems like a reasonable concern.
Perhaps the right solution is to have "fancy" and "lite" admin pages. The "fancy" pages would work like dotLRN and require new-portal. The "lite" admin pages would query the site map for all instances mounted under the current subsite, and link to package-key/admin for each instance. This way we could take advantage of new-portal when it is available, but not require it.
