Many of the features of Pressflow built into core
Huge initial release stability improvements due to using SimpleTest php testing suite (over 30,000 tests).
Taxonomies/vocabularies can be added to entities (users, comments, taxonomy terms, one more I didn't note)
Entities (fieldable objects), bundles (entity subsets) and instances (fields attached to entities)
Files are now objects: document storage possibilities unlocked
http://upgrade.boombatower.com/ and/or coder module help automate module upgrading from D6 to D7
Database abstraction layer: huge improvements. Ability to use any database that php supports.
Dynamic jquery form-building without the pain: don't need to code the javascript
Theming easier and more powerful (with field-able entities giving much finer-grained control)
http://drupal.org/update/theme/6/7 for guide to upgrade themes from D6 to D7
Better media handling: built into core
Usability and accessibility improvements make content administration much easier, more intuitive. Admin overlay keeps the page open where you initiated it (can be disabled if preferred)
Modules can be installed via user interface.

Best, Marilyn

On Mon, Feb 21, 2011 at 8:24 AM, Jamie Holly <hovercrafter@earthlink.net> wrote:

I agree with Larry, especially if you are doing a site for a client.
It's best to put them on the latest version so that they enjoy a longer
support cycle on it, and considering the Drupal 6 support will be
dropped in a couple of years (hopefully), it will keep them happier.

The only real problem you might have with Drupal 7 is if you are just
starting out in Drupal. You won't find as much information out there on
it like you can for Drupal 6, especially if you are doing any custom
development in it. True Drupal has great support lists, so if you run
into a snag you can always get excellent help.

Jamie Holly
http://www.intoxination.net
http://www.hollyit.net

On 2/21/2011 1:38 AM, Larry Garfield wrote:
> Drupal 7's "maturity period" will be far shorter than it was for D6. Drupal 6
> had a very long lag time while contrib caught up. For Drupal 7, we have
> Fields in core, tons of additional functionality in core, VIews is already
> usable on D7, there's hundreds of modules with stable or beta versions for
> D7...
>
> My company (Palantir.net) has been building Drupal 7 sites for over six months
> now. If you know what you're doing, it's ready *today*. There are some
> significant contribs that arent ready, but that's a great opportunity for you
> to jump in and help get them ready. And the knowledge you gain in so doing is
> worth gold to clients looking for someone who can show they really know their
> Drupal.
>
> Unless you need a specific module that's not already ready, and you have a
> tight deadline, Drupal 7 is already mature enough, I'd argue. Drupal 6 was an
> anomaly in that regard.
>
> --Larry Garfield
>
> On Monday, February 21, 2011 12:20:22 am Mutuku Ndeti wrote:
> > Hi,
> >
> > I am using d6 for now until d7 is "mature" enough. This would be about
> > 6 months to one year after launch.
> >
> > All the best.
> >
> > On 2/21/11, Warren Vail<warren@vailtech.net> wrote:
> > > I host better than a dozen Drupal sites, and while I am planning to
> > > switch my dev site to D7 in about 6 mos, if that goes well, I'll begin
> > > to move my client sites when I discover the support for D7 (newer and
> > > better modules) is better than D6. I don't want to expose my clients to
> > > "The Bleeding Edge".
> > >
> > >
> > >
> > > Warren Vail
>
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