Update README, explain differences between nqp and nqp-rx.

README

@@ -1,46 +1,45 @@
 =head1 NQP - Not Quite Perl (6)
 
-NQP is Copyright (C) 2009 by The Perl Foundation.  See F<LICENSE>
+NQP is Copyright (C) 2009-2011 by The Perl Foundation.  See F<LICENSE>
 for licensing details.
 
 This is "Not Quite Perl" -- a compiler for quickly generating PIR
 routines from Perl6-like code.  The key feature of NQP is that it's
 designed to be a very small compiler (as compared with, say, perl6
 or Rakudo) and is focused on being a high-level way to create
-transformers for Parrot (especially hll compilers).  In addition,
-unlike Rakudo, NQP attempts to restrict itself to generating code
-that can run in Parrot without the existence of any NQP-specific
-runtime libraries.
+compilers and libraries for virtual machines (such as the Parrot
+Virtual Machine [1]).  Unlike a full-fledged implementation of Perl 6,
+NQP strives to have as small a runtime footprint as it can, while
+still providing a Perl 6 object model and regular expression engine
+for the virtual machine.
 
-=head2 Building from source
+    [1] http://parrot.org/
 
-NQP comes bundled with Parrot, so if you have a recent Parrot
-distribution you likely also have a copy of NQP.  Inside of a
-Parrot installation NQP is known as C<parrot-nqp>.
+=head2 Building from source
 
 To build NQP from source, you'll just need a C<make> utility
 and Perl 5.8 or newer.  To automatically obtain and build Parrot
-you may also need a subversion (svn) client.
+you may also need a git client.
 
 To obtain NQP directly from its repository:
 
-    $ git clone git://github.com/perl6/nqp-rx.git
+    $ git clone git://github.com/perl6/nqp.git
 
 If you don't have git installed, you can get a tarball or zip
-of NQP from github by visiting http://github.com/perl6/nqp-rx/tree/master
+of NQP from github by visiting http://github.com/perl6/nqp/tree/master
 and clicking "Download".  Then unpack the tarball or zip.
 
 Once you have a copy of NQP, build it as follows:
 
-    $ cd nqp-rx
+    $ cd nqp
     $ perl Configure.pl --gen-parrot
     $ make
 
 This will create a "nqp" or "nqp.exe" executable in the
-current (nqp-rx) directory.  Programs can then be run from
-the build directory using a command like:
+current directory.  Programs can then be run from the build 
+directory using a command like:
 
-    $ ./nqp hello.pl
+    $ ./nqp hello.nqp
 
 The C<--gen-parrot> option above tells Configure.pl to automatically
 download and build the most appropriate version of Parrot into a
@@ -77,21 +76,15 @@ to be executed from the command line.  Each line entered is treated
 as a separate compilation unit, however (which means that subroutines
 are preserved after they are defined, but variables are not).
 
-=head2 Differences from previous version of NQP
-
-* Sub declarations are now lexical ("my") by default, use
-  "our sub xyz() { ... }" if you want package-scoped subroutines.
-
-* The  PIR q<...>;  construct is gone.  Use Q:PIR or pir::opcode(...)
-  instead.
-
-* The mainline code of modules is no longer tagged as ":load :init"
-  by default.  Use  INIT { ... }  for any code that you want to be
-  run automatically at startup.
-
-* Cuddled else's are no longer valid Perl 6, 'else' requires a
-  space after it.
+=head2 Differences from nqp-rx
 
-* Double-quoted strings now interpolate $-variables.
+NQP is the successor implementation of "nqp-rx" [2].  Unlike nqp-rx,
+which aimed to have almost no runtime component whatsoever, this new
+version of NQP accepts that a minimal Perl 6 object metamodel,
+multidispatcher, and regular expression engine are needed on top of
+the underlying virtual machine.  Also, nqp-rx is likely to only run
+on Parrot, whereas we expect NQP to eventually run on other virtual
+machine backends.
 
+    [2] http://github.com/perl6/nqp-rx