what I've understood after some lurking, is:
<b> should be used for markup text without semantic importance, <strong> for strong semantic importance
<i> should be used for language change (in any form), <em> for <em>some damned stress emphasis!!!!</em> (not a language change but something that you will pronounce with more emphasis)
is this correct? can you write please some examples, in simple english?!
thank you in advance
Your examples are basically right, although many would argue your <B> and <I> markup should be done in CSS. Voiceover software, braille readers, and other accessibility tools won't mention to a disabled person about bold text, but they will communicate emphasis.