There are no plans to create a independent 4.0 forum, 4.0 is not a break all upgrade like 3.0 was so there is no need. On the other hand we might create a general / 4.0 upgrade sub forum if the community wants it.
* Upgrading directly from 3.9 to 4.0 is should be possible now (however I have not tested this on final version), now that the upgrade bugs have been fixed.
* Extensions: they need to be upgraded to php5, and you also need to go over code that uses the ez publish api since some changes are done. * Not sure, but wouldn't it be easier to just upgrade the 3.9 database ?
>Can you provide some strategies or simple rules for that? A checklist for porting of extensions would be great.
Some hints here (+ in comments): http://ez.no/developer/news/ez_publish_4_0_0_and_ez_flow_1_0_released A more complete article / doc page will hopefully appear soon..
> How about custom tables, for instance of the ezapprove2 or ezstats extensions?
Just make sure the tables are updated to UTF8 if you don't use it already. But the extensions needs to support eZ Publish 4.0 first..
