The 4400 – The Complete Series will be released on DVD on October 28, 2008 in US. The boxset will include all four season, bonus materials and features from the previously DVD releases. (Source: IGN.com)
Suggested retail price is $99.98, but Amazon.com is taking pre-orders at $66.99, which is a steal for a four season boxset.
The 4400 is a great serie and I can highly recomand it.