Version 53:

General
-------

 - view menu items now have accelerators

 - (<= exp) isn't allowed in beginner. (same for <, >, and >=)

 - print primitive is now setup correctly to print based on the language level

 - paren-matching in semi-colon comments is disabled

 - info panel "running" message is now aligned correctly 
 
 - The check synatax and analyze buttons are now disabled during evaluation

 - library directory now starts in "MZLIB_COLLECTS_DIR/../../lib"
   which is our best approximation to "PLTHOME/lib"
 
 - elevator library can now select more than one floor at a time

Version 52:

General
-------

- The words "running" or "not running" at the bottom of the
  DrScheme frame indicate whether or not work is happening in the 
  user's program. 

- a "Windows" menu has been added which keeps track of the currently
  open drscheme windows.

- the source locations for "load"ed files now match the numbers 
  in the bottom of the drscheme window.

- the thread that evaluations (including execution) take place on is
  the same as the eventspace's main thread, unless the evaluation
  thread is killed. In that case, the eventspace's main thread is
  re-generated, but the execution thread does not.

- The REPL implementation has been cleaned up.

- the turtles window does not survive across executions anymore

- the Quasi-R4RS language level has been renamed to R4RS+

DrScheme Tools/Libraries
------------------------

- new methods on rep:edit%: report-exception-error accepts an exception and
  prints the error message in the console.

- send-scheme is outdated. Use run-in-evaluation-thread instead

- the drscheme:tool^ signature has changed. A new subunit, "basis" has
  been aded and the process-finish struct is now in that subunit. So,
  drscheme:language:process-finish? becomes
  drscheme:basis:process-finish?, etc.
  
  The process-finish structure no longer has a boolean indicating sucess. 
  Instead, an exception is raised.


- the settings for the language have been re-aranged
  - there are two new parameters, exported from the basis
    subunit of drscheme:export^, current-setting and current-vocabulary
    - current-vocabulary contains the vocabulary that zodiac uses to
      perform macro expansion
    - current-setting is bound to a setting struct, which encapsulates
      all of the information about the language level
  - the process-*/zodiac and process-*/no-zodiac proceudres
    are no longer methods and their arguments have changed

Version 51:

General 
-------
- fixed error message for "eq?" and "cons" at beginner level.

- check syntax does not work with an unitialized repl when:
  the source contains define-macro. (won't be fixed in the release)

- eval no longer loops forever in mred vocabulary 

- searching keybindings have changed. There are four distinct actions:
   action1: move keyboard focus to the searching window, opening it if necessary, 
            or if already there search forward
   action2: move keyboard focus to the searching window, opening it if necessary, 
            or if already there search backward.
   action3: search again, in the same direction
   action4: move the focus between the main window, searching window and replacment window
   action5: hide the searching window

The actions are mapped to different keys, based on the platform. 

On unix:
 action1 => control-s, meta-%
 action2 => control-r
 action3 => f3
 action4 => control-i
 action5 => control-g

On the macintosh:
  action1 => command-f
  action2 => command-r
  action3 => command-g
  action4 => command-o
  action5 => command-.

On windows:
 action1 => control-f
 action2 => control-r
 action3 => f3, control-g
 action4 => control-i
 action5 => escape

- turned off the file name printouts on splash screen

  evaluate: 
  (wx:write-resource "mred" "splashMessages" 1 (wx:find-path 'setup-file))
  to turn them back on.

- fixed a bug that caused error messages to be displayed in message
  boxes more often than neccessary. (as opposed to printing in the
  repl)

- parenthesis matching is improved

- The empty list is now called "empty" instead of "null" with the
  constructor style printer.

- The analyze button puts up a dialog saying "please wait, loading",
  now.

- the fonts dialog now shows previews of the selected fonts. You
  still need to restart to see the changes, unfortunately.

DrScheme Tools/Libraries
------------------------

- tools must now import wx names explicitly, as a new first import.

- the parameters interface has changed. Instead getting and setting
  the class, the tool programmer must register a function that
  accepts a class and returns a class. See the manual for more
  details.

- process/zodiac-finish has been renamed to process-finish