I'm having numerous problems installing the -proposed package on Lucid. 

Sometimes the upgrade succeeds, sometimes it fails.  I haven't been able to figure out why yet (I think I'm starting from the same state each time, but maybe there's a file somewhere I'm not considering).

If the package upgrade WORKS:
1) I get the following output:
Preparing to replace nis 3.17-31 (using .../nis_3.17-31ubuntu0.10.04.3_i386.deb) ...
 * Stopping NIS services                                                                                                                                                          [ OK ]
 * Stopping NIS services                                                                                                                                                          [ OK ]
 Removing any system startup links for /etc/init.d/nis ...
   /etc/rc1.d/K18nis
   /etc/rc2.d/S18nis
   /etc/rc3.d/S18nis
   /etc/rc4.d/S18nis
   /etc/rc5.d/S18nis
Unpacking replacement nis ...
Processing triggers for ureadahead ...
Processing triggers for man-db ...
Setting up nis (3.17-31ubuntu0.10.04.3) ...
ypbind start/running, process 18583
ypserv stop/pre-start, process 18612

2) There are several upstart jobs installed in /etc/init: start-ypbind.conf, yppasswd.conf, ypserv.conf, ypxferd.conf
3) Reverting the package to the older version leaves behind the /etc/init/*yp*.conf scripts behind

If the package upgrade FAILS:
1) I get the following output:

Preparing to replace nis 3.17-31 (using .../nis_3.17-31ubuntu0.10.04.3_i386.deb) ...
 * Stopping NIS services                                                                                                                                                          [ OK ]
 * Stopping NIS services                                                                                                                                                          [ OK ]
 Removing any system startup links for /etc/init.d/nis ...
   /etc/rc1.d/K18nis
   /etc/rc2.d/S18nis
   /etc/rc3.d/S18nis
   /etc/rc4.d/S18nis
   /etc/rc5.d/S18nis
Unpacking replacement nis ...
Processing triggers for ureadahead ...
Processing triggers for man-db ...
Setting up nis (3.17-31ubuntu0.10.04.3) ...
ypbind start/running, process 16988
start: Unknown job: ypserv
invoke-rc.d: initscript ypserv, action "restart" failed.
dpkg: error processing nis (--configure):
 subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
 nis
E: Sub-process /usr/bin/dpkg returned an error code (1)
A package failed to install.  Trying to recover:
Setting up nis (3.17-31ubuntu0.10.04.3) ...
ypbind start/running, process 17062
start: Unknown job: ypserv
invoke-rc.d: initscript ypserv, action "restart" failed.
dpkg: error processing nis (--configure):
 subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
 nis

2) Only one upstart jobs is installed in /etc/init: ypbind.conf

3) When I tell aptitude to revert back to the older NIS package, it leaves /etc/init/ypbind.conf behind

In BOTH cases, after a server reboot, NIS doesn't come up correctly.

I was able to get it working by installing (so it fails) moving the ypbind.conf file to /tmp, reverting/installing again (so it succeeds) and then moving ypbind.conf back to /etc/init.  Then after a reboot it worked.