Available updates:
[x] [icon] Pippy
           [description, if available]
           From version 3 to version 4 (Size: 42kB)

           [check for updates] [Install updates]

[x] [icon] CEIBAL activities
           3 activities in this group (Size: xyz kB)

Installed activities:
---------------------

Pippy, v2
Downloaded: 08/23/2001
Author: XYZ

New Version available!

Get More
--------

* Groups file lists groups in order, with final 'catch all'.
  If don't want to update by default, don't list catch all?
* Separate 'pin' option in microformat.
* cmd-line interface to updates lists available updates, lets you
  install individually or 'all'.

group 1... group 2...activity update_url ... default group.

if no activities, then default to .group 

** add a sugar alert if there were network errors while looking for
   updates.