Ask HN: Joomla vs Drupal (vs Magento)?

I am looking for opinions on which CMS is 'most appropriate' for creating reasonably sophisticated websites, sometimes with e-commerce functionality. The team creating the site is a combination of designers and developers, but the end-user could be anyone.

From what I hear, Joomla is quick and easy to set up but doesn’t seem as 'industrial' or extensible as the Drupal. I read that Drupal has a steeper learning curve, but does that just mean non-techies will struggle with it? We’re developers, so not bothered about coding, and from my initial investigations in to Drupal it doesn’t look too tricky. Also, the plugins look to deal with a lot of common website requirements. Including Ubercart for e-commerce. Magento is a (relatively) new e-commerce specific CMS, but I worry that it isn’t as widely used (read: tested) as Drupal and that it won’t have the same pool of plugins available.

I’ve read a fair bit about each but guess this is quite a common dilemma - it’s a considerable investment to learn, implement, integrate and maintain a new CMS - so am posting it here. As ever, the right solution ultimately is dependant on the specific project, but it would be interesting to hear some thoughts on each.