On 8 March, the US Senate passed the Trademark Dilution Revision Act 2006. The Act introduces a likely dilution standard (instead of actual dilution), new definitions of blurring, tarnishment and famous marks (marks must be famous to qualify for actual dilution protection).
The Act is a revised version of the Bill that formed the Trademark Dilution Revision Act 2005. The 2006 version is almost identical to the 2005 version, but it introduces a general defence of non-commercial use and a special burden of proof for trade dress dilution cases.
More details here.