As with Google Maps, Virtual Earth does not support all of the KML spec, and this should not be a surprise: VE has abilities that KML cannot cater for, and vice versa.

Anyway, somewhere I saw a list of what is and isn't support but cannot find it now.
I've found another item for the list: The KML spec says that Placemarker Descriptions can include HTML, and that CDATA is recommended for readability.

Unfortunately, it looks like VE is ignoring HTML or some HTML -
tags are ignored.
Google Earth and Google Maps interpret these correctly.
(pure text newlines are ignored by VE and GM - as pure HTML should do).


Richard