The one point I'd like to make is that Microsoft has never threatened to sue anyone over Mono. They made an official agreement with Novell to appease Novell's

The one point I'd like to make is that Microsoft has never threatened to sue anyone over Mono. They made an official agreement with Novell to appease Novell's corporate customers but that doesn't mean they'll sue anyone else. In fact, just the opposite. Scott Guthrie (VP of Development at Microsoft) regularly gives time on his popular blog to Mono projects (see one example: http://weblogs.asp.net/scottgu/archive/2009/02/11/moonlight-1-0-release.aspx http://weblogs.asp.net/scottgu/archive/2009/02/11/moonlight-...) The whole "Microsoft Patent" issue is based on the Free Software Foundation stating a concern that Microsoft could someday sue. I don't dispute that concern but understand Mono is very much in Microsoft's best interest because it competes with Apache on Linux. Finally, as the article points out, even if Microsoft asserts it's patents they'll only be taking away certain support functions like ADO.NET. The heart of Mono is the C# compiler which is an ECMA and ISO standard.