From the documentation at http://docs.vagrantup.com/v2/getting-started/project_setup.html

"The Vagrantfile is meant to be committed to version control with your project, if you use version control. This way, every person working with that project can benefit from Vagrant without any upfront work."

The old pattern was too broad and was making VIM ignore Scheme (*.scm) files.
Now it only matches files that start with . or _.

Documented at http://docs.vagrantup.com/v2/getting-started/project_setup.html

These files are created automatically the first time a vagrant box is started.

As is clearly stated in the [eclipse documentation](http://wiki.eclipse.org/FAQ_How_do_I_set_up_a_Java_project_to_share_in_a_repository%3F).  
This gitignore has lead to much confusion in SO - please ammend

I would guess the same is true for .pydevproject and .cproject but can't
be sure/do not have any references on those

Also .launch configurations are generally meant to be versioned when
saved under project location. See for instance :
http://stackoverflow.com/a/337317/281545

.*.s[a-w][a-z] matches named swap files.
.s[a-w][a-z] matches unnamed swap files.

Because files and directories starting with a `.` are not ignored in general.

Vim creates buffer swapfiles starting at .swp for buffers that are
active but untitled and unsaved.

Changed line matching vim swapfiles to use all names it will create as described in http://vimdoc.sourceforge.net/htmldoc/recover.html#E326

See http://en.wikipedia.org/wiki/Windows_thumbnail_cache#Thumbs.db

It contains project specific configuration, and should therefore by
checked into version control (as documented on
http://www.sublimetext.com/docs/2/projects.html)

KDevelop4 is the C/C++-IDE from the KDE desktop.
It creates a directory '.kdev4' and a hidden file
<projectname>.kdev4 in the project's root directory.

Include .netrwhist, the user's history and potential privacy concern. See: http://stackoverflow.com/questions/9850360/

Including mexglx, mexa64, mexmaci64, mexw32 & mex64 (see
http://sfwn.in/FxbE for official list from Mathworks).