I get a capture card around the start of the new year (for real now, I'm not just talking about it, I got my shippin order!). I'm looking forward to posting some video's of these things in action.
It's about 150 magic AR boosted onto your weapon. For the low cost of 10 int, with 5 casts, well worth it if you just need a small boost to your damage to get through the area. It's good for giving yourself a bit of chip damage in PvP, but don't expect it to perform miracles for you.
Yeah, MW is essentially a resin that gives you magic damage. GMW is a good buff though with the Oolacile cat, 200 extra AR makes quite a bit of a difference.