diff --git a/CONTRIBUTORS b/CONTRIBUTORS
index 7c54b88cbcd6535e703936f04a7ec2b2fd23db01..bb1f6853815b26cc4ac44b94b2e5f853074beaaf 100644
--- a/CONTRIBUTORS
+++ b/CONTRIBUTORS
@@ -7,32 +7,43 @@ or send a pull request.
 
 Contributors include:
 
-Mininet Core Team
+Mininet Core Team (and alumni)
 
 Bob Lantz
 Brandon Heller
 Nikhil Handigol
 Vimal Jeyakumar
 Brian O'Connor
+Cody Burkard
 
 Additional Mininet Contributors
 
+Tomasz Buchert
 Gustavo Pantuza Coelho Pinto
+Fernando Cappi
 Ryan Cox
 Shaun Crampton
 David Erickson
 Glen Gibb
 Andrew Ferguson
 Eder Leao Fernandes
+Gregory Gee
+Jon Hall
 Vitaly Ivanov
 Rich Lane
+Zi Shen Lim
 Murphy McCauley
 José Pedro Oliveira
 James Page
+Rich Lane
+Rémy Léone
 Angad Singh
 Piyush Srivastava
 Ed Swierk
+Darshan Thaker
+Andreas Wundsam
 Isaku Yamahata
+Baohua Yang
 
 Thanks also to everyone who has submitted issues and pull
 requests on github, and to our friendly mininet-discuss
diff --git a/INSTALL b/INSTALL
index 6d6337fde7175ae5c562b936322f30bf50a6f4f8..6366951111bc31fa96a0f68385778132c97c85dc 100644
--- a/INSTALL
+++ b/INSTALL
@@ -2,7 +2,7 @@
 Mininet Installation/Configuration Notes
 ----------------------------------------
 
-Mininet 2.1.0+
+Mininet 2.2.0b0
 ---
 
 The supported installation methods for Mininet are 1) using a
diff --git a/LICENSE b/LICENSE
index 0cb01dd0c9e9bf1a4aca5ab18f9939ef5fb0d550..8c32cbe5e204247acac5129d621d72d2bff34508 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,4 @@
-Mininet 2.1.0+ License
+Mininet 2.2.0b0 License
 
 Copyright (c) 2013 Open Networking Laboratory
 Copyright (c) 2009-2012 Bob Lantz and The Board of Trustees of
diff --git a/README.md b/README.md
index 4c668ae85682a8c98a28b3124c3ce2003a79e478..8caa7184d31f7c9ac0e79d0fbd9fd188725ae917 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@ Mininet: Rapid Prototyping for Software Defined Networks
 
 *The best way to emulate almost any network on your laptop!*
 
-Version 2.1.0+
+Version 2.2.0b0
 
 ### What is Mininet?
 
@@ -66,28 +66,32 @@ Mininet includes:
 
   `mn -c`
 
-### New features in 2.1.0+
+### New features in this release
 
-Mininet 2.1.0+ provides a number of bug fixes as well as
+This release provides a number of bug fixes as well as
 several new features, including:
 
-* Convenient access to `Mininet()` as a dict of nodes
-* X11 tunneling (wireshark in Mininet hosts, finally!)
-* Accurate reflection of the `Mininet()` object in the CLI
-* Automatically detecting and adjusting resource limits
-* Automatic cleanup on failure of the `mn` command
-* Preliminary support for running OVS in user space mode
-* Preliminary support (`IVSSwitch()`) for the Indigo Virtual Switch
-* support for installing the OpenFlow 1.3 versions of the reference
-  user switch and NOX from CPqD
-* The ability to import modules from `mininet.examples`
+* Improved OpenFlow 1.3 support
 
-We have provided several new examples (which can easily be
-imported to provide useful functionality) including:
+	- `mn --switch ovs,protocols=openflow13` starts OVS in 1.3 mode
+	- `install.sh -w` installs 1.3-compatible Wireshark dissector using
+	  Loxigen
+	- `install.sh -y` installs Ryu 1.3-compatible controller
 
-* Modeling separate control and data networks: `mininet.examples.controlnet`
-* Connecting Mininet hosts the internet (or a LAN) using NAT: `mininet.examples.nat`
-* Creating per-host custom directories using bind mounts: `mininet.examples.bind`
+* A new `nodelib.py` node library, and new `Node` types including
+  `LinuxBridge`, `OVSBridge`, `LinuxRouter` and `NAT`
+
+* An improved MiniEdit GUI (`examples/miniedit.py`) - thanks to
+  Gregory Gee
+
+* Experimental cluster support - consult the documentation for details,
+  as well as `examples/cluster.py` and an experimental `--cluster`
+  option for topologies built with the default `Host` and `OVSSwitch`
+  classes:
+
+  `mn --cluster localhost,server1,server2`
+
+[1] http://docs.mininet.org
 
 Note that examples contain experimental features which might
 "graduate" into mainline Mininet in the future, but they should 
@@ -113,21 +117,27 @@ Mininet mailing list, `mininet-discuss` at:
 
 <https://mailman.stanford.edu/mailman/listinfo/mininet-discuss>
 
-### Contributing
+### Join Us
 
 Mininet is an open source project and is currently hosted
 at <https://github.com/mininet>.  You are encouraged to download
 the code, examine it, modify it, and submit bug reports, bug fixes,
 feature requests, new features and other issues and pull requests.
-Thanks to everyone who has contributed to the project
-(see CONTRIBUTORS for more info!)
+Thanks to everyone who has contributed code to the Mininet project
+(see CONTRIBUTORS for more info!) It is because of everyone's
+hard work that Mininet continues to grow and improve.
+
+### Enjoy Mininet
 
 Best wishes, and we look forward to seeing what you can do with
 Mininet to change the networking world!
 
-### Credits
-
-The Mininet 2.1.0+ Team:
+The Mininet Core Team:
 
 * Bob Lantz
 * Brian O'Connor
+* Cody Burkard
+
+Thanks again to all of the Mininet contributors, particularly Gregory
+Gee for his work on MiniEdit.
+
diff --git a/mininet/net.py b/mininet/net.py
index 8f89babbab21c1b149a13e2271d833ddf286d67e..83ad1ae7f753b3d86b980d42912d229a7cde6490 100755
--- a/mininet/net.py
+++ b/mininet/net.py
@@ -106,7 +106,7 @@
 from mininet.term import cleanUpScreens, makeTerms
 
 # Mininet version: should be consistent with README and LICENSE
-VERSION = "2.1.0+"
+VERSION = "2.2.0b0"
 
 class Mininet( object ):
     "Network emulation with hosts spawned in network namespaces."
diff --git a/util/versioncheck.py b/util/versioncheck.py
index 7180f4935f56a5f622990839e1b44e30e6cc47a5..94f5579512caad8be98c71e575b524d90dcc01c0 100755
--- a/util/versioncheck.py
+++ b/util/versioncheck.py
@@ -8,7 +8,7 @@
 version = version.strip()
 
 # Find all Mininet path references
-lines = co( "grep -or 'Mininet \w\+\.\w\+\.\w\+[+]*' *", shell=True )
+lines = co( "egrep -or 'Mininet [0-9\.]+\w*' *", shell=True )
 
 error = False