I've stuck a version (5.8b3) of the cocoa based os-x squeak cog JIT based VM in my experimental folder. 

http://homepage.mac.com/johnmci/.Public/experimental/Squeak%205.8b3.app.zip

This VM is built from the Cog sources (with some minor changes for the iPhone) & revised & fixed Socket Plugin. 
It currently does NOT contain any external plugins.  I did check in the changes to squeakvm.org that are required to 
build this VM excluding the required Cog changes... 

People are invited to take it for a whirl, report any performance gains, issues and especially crashes.

PS 

(a) yes shortly we'll get the iPhone changes folded back into the source tree so you can build the VM. 
(b) yes when resizing a window you get neat graphic effects (fixing that issue is non-trival). 
(c) As time permits we'll look into rebuild this rather long list of plugins. 

ClipboardExtendedPlugin.bundle
CroquetPlugin.bundle
CurlPlugin.bundle
FloatMathPlugin.bundle
FT2Plugin.bundle
IA32ABI.bundle
KedamaPlugin.bundle
KedamaPlugin2.bundle
LocalePlugin.bundle
mpeg3Plugin.bundle
ObjectiveCPlugin.bundle
OggPlugin.bundle
PrintJobPlugin.bundle
QuicktimePlugin.bundle
RomePlugin.bundle
SerialExtendedUnixPlugin.bundle
ServicesPlugin.bundle
SpellingPlugin.bundle
SqueakFFIPrims.bundle
TestOSAPlugin.bundle
UnixOSProcessPlugin.bundle

--
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John M. McIntosh <johnmci at smalltalkconsulting.com>   Twitter:  squeaker68882
Corporate Smalltalk Consulting Ltd.  http://www.smalltalkconsulting.com
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