Sony did it earlier this year, why not Microsoft? Note that this doesn't apply to Canadians as it's illegal here.
If you want to opt out, this bit is relevant:
" As with other similar terms of service changes, users may choose to reject it by sending a letter (a paper one) to Microsoft Corporation, ATTN: LCA ARBITRATION, One Microsoft Way, Redmond, WA 98052-6399."
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ICON:
Can I kick it?