I'm pretty sure the iPad does not support embedded fonts. What is confusing to some people though, is iBooks shows a very small selection of fonts in its font selection popover. But that isn't the entire list of fonts iBooks supports. The entire list is here:
http://www.pigsgourdsandwikis.com/20...s-on-ipad.html
So if you are seeing fonts that aren't in the iBooks list, it could be one of these being called in the CSS alternatives, or iBooks is replacing it on its own.
P.S. What are SVG fonts? Because someone posted that those are supported?