Windows developed an extension that lets them do conflict resolution in the web. We have a server-side API that it calls into, but the extension isn't fundamentally different from using BeyondCompare or $YOUR_FAVORTE_MERGETOOL.
I thought the three way merge tool was independent of the source control system. I'm pretty sure that's true for the four systems I've used: hg, tfs, perforce, and the horrible horrible SLM. I can say however that SLM's default three way merge just seemed to always do the right thing.
Tools for managing real conflicts seem more interesting. Most conflict resolution tools seem to 'help' in a way that leaves me completely baffled. They automate the creation of unintentional edits rather than helping you understand the history of the changes that lead to the conflict, and tracking and reversibility of what you are doing during merge.
I've resorted to temporarily overlaying another source control system to track dealing with resolving large complicated merge conflicts.
That's really cool. I use their tool p4merge for diffing and merging for TFS (shh) and git and it's awesome. They offer it as a separate download, would be great if they opensourced this :D
I personally like them for resolving merge conflicts by hand. It really helps just clicking on a section in blueish to instantly jump to a conflict in large-ish files.
Currently if a conflict occurs it’s reported back to the client that triggered it and its up to it to resolve it. We are currently working on configurable merge strategies on a per record level
As someone who moved from perforce to VS/TFS2010 at work, the first thing everyone at the office demanded back was p4merge. It's a very good tool.
Fortunately, with VS2012 the built in merge-tools has become much better and allows you to do inline editing in the basic compare/merge-view as well. Since VS2012, I can't say I don't miss p4merge, but I miss it a lot less.
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