Thank you for pointing this out. It's not a problem for a lot of people but the fundamental ethics driven FOSS user should at least be made aware that he sided with Microsoft during the worst Linux is cancer era of MS PR.
"Advocacy of Microsoft open technologies edit
De Icaza endorsed Microsoft's Office Open XML (OOXML) document standard,[15][16][17] disagreeing with a lot of the widespread criticism in the open source and free-software community.
He also developed Mono – a free and open-source alternative to Microsoft's .NET Framework – for GNOME.[18] This has raised much disagreement due to the patents that Microsoft holds on the .NET Framework.
De Icaza was criticized by Richard Stallman on the Software Freedom Day 2009, who labeled him as "Traitor to the Free Software Community".[19] Icaza responded on his blog to Stallman with the remark that he believes in a "world of possibility" and that he is open for discussions on ways to improve the pool of open source and free software.[20]"
Complicated man. I wouldn't want his legacy.