The Content Query Web Part is the Out-of-Box content roll-up web part in MOSS, and consequently it’s one of the most widely used.
It’s advantages are:
- Can select from an entire Site Collection, a Site and it’s Sub-Sites, or from a List
- Can select by List type
- Can filter the results by Content Type, or Metadata field values
- Can be configured to do Sorting and Grouping
- Can display custom data – but this is a little complex
It’s disadvantages are:
- Customising the view is possible, but tricky.The view has to be defined in XSL, and the Content Query Web part configured correctly to get the data you want to display.
- No pagination of results – it’s just truncated.
- The user can’t select the results order, or add his own filter.
- You can’t query across Site collections.
All in all, I’d say that defining the styles for what you want to display puts this into more a ‘development’ task, which isn’t ideal if you’re trying to push administration out to your users a bit more.
Also, a major issue as far as I’m concerned is the lack of pagination. You can limit the number of items shown, but without an link to the next ‘page’ of items.
Here’s an example of a Content Query Web Part showing some custom data (highlighted in yellow):
In short: Cheap, and available, but has that ‘just a bit awkward’ feel to setting it up, and lacks some of the features you’re likely to want. Often will require someone a bit technical for customisation.