1. How does the card stand on its own? Is it good, bad, or have potential? Is it worth being played?
palkia G Lv X is a beast. It has gotten a lot of trouble in the form of it's weakness (Luxray says hi!), but otherwise the card is pretty solid! It has a good sniping attack which can abuse DCE, and it's power can be both beneficial for you as well as disruptive for your opponent.
2. What popular metagame decks is it used in?
Palkia Lock, Palkia G/Dialga G, PG-13, rogues(?)
3. What combos can you use it with? How so?
Mesprit LA, Azelf LA, Uxie LA, Giratina (Let Loose), any kind of ''useless afterwards'' one time only poké-power pokémon. It also works well in general, but requires some specific deck-requirements (ie, either it's power or attack should assist the goal of the deck, it's no card to randomly splash into anything). Just watch out with it's power in the future when Lost World comes out!!
4. Give it a rating, and explain why you have given it that rating. You can also rate the card by rating the thread itself (out of 5 stars).
6.5/10, mainly because Luxray is so ''big'' right now, otherwise I'd have no problem at all to rate it 8/10 at least.
5. How's the artwork?
I find it rather beautiful and like it a lot! But of course, that's just me.
EDIT: w00t, first!!