The shadow dancer says its caster level is equal to the shadow dancer's level.
Is this the current level of the PRC or is this the whole level of the character?
Current level of the PrC; unless otherwise specified, it is never the character level.
dang.. that sucks pretty hard. No wonder people just dip it.
Yep, but there are some classes that do specify character level, like the "lantern bearer". But yeah, considering that their abilities are all based around DC-centric spells, it's SLAs seriously suck. If you want, you can try to comvince your GM to rule otherwise (I would probably accept it), but it's not a given.
Well, depends on what you want from the PrC--I've never heard before anybody taking it for its spellcasting, but the other class features might augment the "chassis" quite well and it certainly adds a lot of flavor.
Looking at the shadow dancer the utility you gain from the shadow xyz spell-like abilities is quite amazing for a martial-based char.
Ruyan.