Re: What a modern collaboration toolkit looks like

[Richard Stallman]

    In modern DVCSes, a push never blocks. The sequence of changesets you
    developed is grafted into the repo as a branch attached to the
    revision you pulled from.

    If no one else has committed or pushed against that revision, the line
    of development remains linear.  If someone has, you have the analogue
    of a CVS conflict -- the revision is now a branch point with two
    histories going forward.  

    Later, someone may do a merge operation that fuses those two branches
    together again.  Thus, "commit-before-merge".

I think I understand that now, but it raises other questions.

Does this mean there is no concept of "trunk"?  When someone who is
not normally a participant in the project decides to "download the
current sources", which revision does he get?  More precisely, what
determines which revision he gets?

The operation analogous to a CVS commit to the trunk
would consist of pushing a new revision and then
whatever else is needed to make that revision the new trunk.