Drupal
Advantages
- Very clean core code.
- Good project leadership from Acquia.
- Can be made very server efficient in the right hands (scaleable).
Disadvantages
- Less ready made drop-in plugins.
- More imposing default user interface.
Joomla
Advantages
- Good menu system.
- Strong static page structure.
- Built-in membership/community features.
- Long time on the market.
Disadvantages
- Built-in performance pretty sluggish/clunky.
- Horrid built-in URLs.
- Weak weblog section.
- Hard to theme.
- Nasty core code. Very difficult to fix broken items.
- Fractured community.
- Most good plugins are paid.
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