Post 1.6.3 MaintNotes updates

MaintNotes

@@ -92,7 +92,7 @@ but they are not expected to be anything major, and more
 importantly quickly and trivially fixable.  Every now and
 then, a "feature release" is cut from the tip of this branch and
 they typically are named with three dotted decimal digits.  The
-last such release was 1.6.2 done on Mar 3rd 2009.  You
+last such release was 1.6.3 done on May 6th 2009.  You
 can expect that the tip of the "master" branch is always more
 stable than any of the released versions.
 
@@ -101,7 +101,7 @@ from "master" at that point.  Obvious, safe and urgent fixes
 after a feature release are applied to this branch and
 maintenance releases are cut from it.  The maintenance releases
 are named with four dotted decimal, named after the feature
-release they are updates to; the last such release was 1.6.1.3.
+release they are updates to; the last such release was 1.6.2.5.
 New features never go to this branch.  This branch is also
 merged into "master" to propagate the fixes forward.
 
@@ -227,16 +227,18 @@ relying on heavily:
 
  - Alexandre Julliard on Emacs integration.
 
- - Charles Bailey for git-mergetool (and Theodore Ts'o for creating
-   the tool).
+ - Charles Bailey for taking good care of git-mergetool (and Theodore
+   Ts'o for creating it in the first place).
+
+ - David Aguilar for git-difftool.
 
  - Johannes Schindelin, Johannes Sixt and others for their effort
    to move things forward on the Windows front.
 
  - People on non-Linux platforms for keeping their eyes on
    portability; especially, Randal Schwartz, Theodore Ts'o,
-   Jason Riedy, Thomas Glanzmann, Brandon Casey, but countless
-   others as well.
+   Jason Riedy, Thomas Glanzmann, Brandon Casey, Jeff King,
+   Alex Riesen and countless others.
 
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