The main downside with this bonus is that they require you to pay for checks (at least when opened online), and the minimum cost for checks is $17.50. If you can find a way to avoid this cost, it looks to be an easy $50.
They have long offered this $50 promotion. My last post
on this was in January 2009. One improvement is that the bonus is now a cash credit to your account rather than a gift card.