Joomla has been lagging behind the curve for some time now. They have tried to change this with their new 1.5.x releases and I understand that this new branch has done much to address the issues that Joomla has had for a long time, but they already lost me before that.
From a hackers POV who is interested in maximum flexibility, and using the most modern tools for the job that also promote standards compliance, I think there are much better options out there, such as Drupal (staying in the LAMP space). Joomla just feels more clunky and legacy to me than other options. I also really disliked past experiences I've had with the Mambo CMS and Joomla is a fork of Mambo. There is also more of an "industry" around selling add-on modules and templates for Joomla, where as just about all modules/templates for Drupal are free (as in speech and beer).
Joomla would be "as easy to update as a blog" if all you are using it for is to run a blog. But to be fair, this is generally true of Drupal and other similar offerings as well.
Neither Joomla or any other CMS is a "SEO miracle, bringing search results up several ranks just [by] being installed" this is complete bullshit. It comes down entirely to how the template that the site will use has been designed, how the content of the site is organised, marked up and optimised, and all the other normal issues that surround SEO. How well all this comes together of course comes down to whether the people doing the design/development know what they're doing.
From a "business guy" POV - who assumedly cares little for such things as standards compliance and maximum flexibility (he has a specific function to fill only) - in the end, There would not be a lot of difference between Joomla and another similarly featured CMS, as long as the guys providing the technical skills know their shit. Depending on your priorities, Joomla is not inherantly crap, nor is any other CMS a magic bullet. Just make sure that these guys offering services to your friend are of the afore mentioned type who know their shit.
But to me, if someone is recommending Joomla as their primary offering, this does not inspire confidence in me that the people doing the recommending have their "finger on the pulse" as it were.