Drupal 7?

I'd say Drupal 7, at this stage is suitable if you're familiar with Drupal. For as many improvements it has, it introduces some logistical problems. Drupal 7 is updating quite frequently, and new critical bugs are being found... this means you will need to be updating your site frequently, and updates might cause problems (depending on modules or themes you use). Also... It depends on how complex your site is going to be, and what modules you need. As Hitler points out in the video, you won't have modules like Panels available. So for simple needs it might work perfectly, as long as you know how to maintain your site.

I work for Acquia, but even if I didn't I'd recommend using DrupalGardens - because you can essentially pay someone else to do your updating and upgrading for you. There is a free package, but even with the paid upgrade to a custom URL, etc, it's still good value.

There's also things you can do to make the admin area look nicer in your Drupal 6 site. Use a specially designed administration theme. To do this:

Navigate: Site configuration > Administration theme.

Here you can set and administration theme for site configuration as well as content editing.
Module highlight: Better administration

Admin Menu module
http://drupal.org/project/admin_menu

http://drupal.org/project/admin 
You can combine the Admin module with an administration theme, such as Rubik & Tao to make a completely separate administration area with user friendly icons & shortcuts.
http://drupal.org/project/rubik (depends on Tao http://drupal.org/project/tao )

As an easy alternative, RootCandy provides a complete administration theme providing a clear separation between front end and administration. http://drupal.org/project/rootcandy

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