Agreed. I set up a bitstamp account just recently with a view to do some arbitrage.
Having done the sums though, it's a no go for me unless the price gap widens. Hefty fees and exchange rate spreads (my home currency is not the US dollar), combined with a ridiculous amount of time spent before the money comes back to your account thanks to slow wire transfers by Gox, just doesn't make arbitrage possible...at these prices.
I'd been using Dwolla until last week, and I hadn't realized how slow wire transfers from Gox were. I thought 4 days, tops, but apparently it will take a lot longer than that.
Being american does help though, you can arbitrage narrower exchange BTC/USD spreads since you don't get hit with daylight robbery bank exchange rates (another 3% markup over market rates, in my case) to convert back to your home currency.
Good point - I'm American, so forgive me if I forget about the rest of the world.
I also have a 0.29% trading rate at Gox, and after buying a few hundred coins should have a 0.2% rate at Bitstamp, so the math works for me: $118*1.0059 = $118.70, a $3.5/bitcoin profit. The wires are flat fees, a small % with five figure sums.
The only question is if the spread will persist until my Gox wire appears. If it doesn't, I thankfully won't lose anything, I just won't gain.