Updated the release announcement.

ANNOUNCE

@@ -6,13 +6,29 @@ libobjc2).  This runtime was designed to support the features of Objective-C 2
 for use with GNUstep and other Objective-C programs.  Highlights of this
 release include:
 
-- Compatibility with the new runtime APIs introduced with Mac OS X 10.7.
+- Compatibility with the new runtime APIs introduced with Mac OS X 10.7 / iOS 5.
+
 - Support for small objects (ones hidden inside a pointer).  On 32-bit systems,
   the runtime permits one small object class, on 64-bit systems it permits 4.
+  This is used by GNUstep for small NSNumber instances, and these are used by
+  LanguageKit for message sending to small integers.
+
 - Support for prototype-style object orientation.  You can now add methods, as
   well as associated references, to individual objects, as well as cloning
   them.  The runtime now supports everything required for the JavaScript object
-  model, including the ability to use blocks as methods.
+  model, including the ability to use blocks as methods on x86, x86-64 and ARM.
+
+- Support for Apple-compatible objc_msgSend() functions for x86, x86-64, and
+  ARM.  Using these approximately halves the cost of message sending operations
+  and results in a 10% smaller total binary size.  
+
+- A fully maintained POSIX Makefile to make bootstrapping builds and packaging
+  easier.
+
+Various features of this release required some per-platform assembly code.  For
+the 1.6.0 release, ARM, x86 and x86-64 (with the SysV ABI, not with the Win64
+ABI) are supported.  Future releases in the 1.6.x series will extend this to
+other architectures.  
 
 You may obtain the code for this release from subversion at the following
 subversion branch: