#817216 by ctmattice1, chx, Stevel, Damien Tournoud: Fixed system_update_7008 does not work, deal with invalid poll choices, and move poll-related upgrade logic to Poll module.

#829378 by David_Rothstein: Fixed Update system should use the API to identify the install profile, rather than preg_match().

- Patch #692044 by Damien Tournoud, effulgentsia, jbrown: a site with statistics module enabled is much slower in serving cached pages in D7 than in D6.

- Patch #692044 by Damien Tournoud, effulgentsia: a site with statistics module enabled is much slower in serving cached pages in D7 than in D6.

- Patch #228860 by tstoeckler, Mike Wacker, flickerfly, randallknutson, gordon: upgrading a module with a newly added dependencies breaks things badly.

#551658 by pwolanin, aaron, drewish: Move private files to an opt-in system, and no longer force private files to live within web-accessible directory.

- Patch #741578 by nikgregory, andypost, Berdir, noahb: 'File' is a reserved word that should not be used.

- Patch #728338 by sun, Crell: standardize on 'field' in function names. 'It has to get worse before it can get better.'

#734742 by Damien Tournoud: Upgrade path: no need to change the definition of the {url_alias()} table twice.

- Patch #358315 by neochief, andypost, Damien Tournoud, catch, xurizaemon: drupal_lookup_path() not respects alias' order.

- Patch #279851 by catch, David Strauss, Damien Tournoud, asimmonds, c960657, JohnAlbin, drawk, pwolanin, robertDouglass, coltrane: replace LOWER() with db_select() and LIKE() where possible.

- Patch #641408 by cha0s, David_Rothstein: PHP extensions and PDO functionality should be checked at installation.

#716348 by grendzy and hefox: Documentation of drupal_get_path() and system table missing the fact that 'profile' is stored there now.

#211182 by Damien Tournoud, David_Rothstein, clemens.tolboom, scor, hunmonk, et al: Allow updates to specify dependencies to ensure they run in a predictable order.

- Patch #563106 by adrian, David_Rothstein: more upgrade path fixes to help contrib updates make progress.

#679890 follow-up by Bojhan, aspilicious, and agentrickard: Remove more extraneous 'Please' in the interface.