I've noticed that Atlassian was holding a Summit yesterday. Apparently it was a success with 2100 attendees. That's great to see and I wanted to congratulate them on that!.
As a developer on the XWiki project what sparked my interest were the announcements related to Confluence. Although I haven't viewed the video yet (it wasn't posted when I checked), I've gathered the following from tweets and blog posts I've noticed:
- New File Collaboration:
"You’ll be able to share files through Confluence and collaborate on them in much the same way you already do with pages, using @mentions and in-line comments.
- Real time collaborative editing:
And it’s not uncommon for two or more people to need to make updates to the same page at the same time. That’s why we’re bringing real-time collaborative editing to Confluence. (yes!) Timeframe for delivery is a bit nebulous at this point, but the dev team is already plugging away on it
- Inline comments on highlighted text:
Oh, and in-line commenting? Yeah, that’s coming to Confluence pages in 5.7, too.
These are all very nice features. Actually they're so nice that the XWiki project has been working on them for some time too, some being there for years and some being more recent. So here's how XWiki would compare on those features:
- File Collaboration. We have a very nice File Manager allowing users to easily import lots of files inside XWiki, manage them inside the wiki. You can comment on files, tag them, add wiki content related to the files, and more.
- Real time collaboration. We have been working on years on real time collaboration in partnership with Academia (INRIA to be precise). We wanted to have realtime for both the Wiki editor and also the WYSIWYG editor. We've tested various solutions and in the end we've found some algorithms that seem to work well. Thus we now have 2 extensions for Real time:
- Inline comments. XWiki has had support for Annotations for years now (4 years to be precise), allowing users to select text and put an annotation on that text. You can even reply to annotations and they are resilient to reasonable changes from the highlighted content!
IMO this shows several things:
- The open source XWiki project is keeping its innovation rate and is still ahead in term of features
- A small team can do miracles (the XWiki dev team is much smaller than the Confluence one)
Go XWiki, go! 
