Legal worries? He means they want to see the US patent system destroyed, and this is their way of circumventing it.
No, he means, "the exceptions to the 'royalty-free license ... to make, use, sell, offer to sell, import, and otherwise distribute Licensed Implementations solely for the purpose of reading and writing files that comply with the Microsoft specifications for the Office Schemas' are problematic, as are the terms of use"
MS wants to own the file format whereas MA prefers the taxpayer's information be stored in a non-proprietary format so that any vendor can participate in future state information technology contracts. Should MA be locked into a single vendors proprietary format, or locked into an open format that anyone can create programs to read and write? Which situation do you think is better for free market competition?
If you're genuinely interested in the subject and not just spreading FUD for MS you could read this article: http://www.eweek.com/article2/0,,1863229,00.asp