I'll admit it now: when it comes to hardcore XML schemas,xsd's, DiffGrams and all that stuff - my eyes glaze over. Its something that I know I'll have to get into someday, but right now I'm mostly a bystander looking at all the cool traffic go by. My mind is currently occupied with enough as it is.
However, if I'll ever need to get into that stuff, I'll know what blog to start from: Oleg's blog. Oleg is an XML MVP and there is some serious stuff floating on there. If you are into this, you should definitely subscribe. And no, I'm not writing this simply because he's another Israeli Blogger :)