Squid 3.2 represents a new feature release above 3.1.
The most important of these new features are:
CVE-2009-0801 : NAT interception vulnerability to malicious clients.
NCSA helper DES algorithm password limits
SMP scalability
Helper Multiplexer and On-Demand
Helper Name Changes
Multi-Lingual manuals
Solaris 10 pthreads Support
Surrogate/1.0 protocol extensions to HTTP
Logging Infrastructure Updated
Client Bandwidth Limits
Better eCAP support
Cache Manager access changes
Most user-facing changes are reflected in squid.conf (see below).