I don't know if it's possible to say on a '%' scale. I'd recommend
looking at the list of API changes yourself:
http://drupal.org/update/modules/6/7
http://drupal.org/node/394070
There looks like a lot of changes, but they aren't too bad, really.
Perhaps your best bet is to try your best, and run whatever code you
write through the coder module, which should pick up on any API changes
you missed and point them out to you.
The biggest changes are DBTNG and the Fields API:
http://api.drupal.org/api/group/database/7
http://api.drupal.org/api/group/field/7
Brian
Jeff Greenberg wrote:
I'd be interested in hearing opinions, on a % scale, of how much
reeducation is needed to move from D6 to D7 in terms of the api,
hooks, architecture, admin functions... for a D6 developer to be at
the same level of capability with D7.
