Twitter and American Express announced a curious new partnership on Monday: a program that lets you buy things like jewelry and electronics by tweeting out a specific hashtag. Our first reaction was visceral. Is buying stuff — expensive stuff! — via tweet a bad idea? Or is it the worst idea ever? That all depends on how open-minded you want to be about the purpose of social media.

The Twitter-Amex program actually sounds dead simple. It's not dissimilar to a scheme the two companies launched last year called "Twitter Offers" which used Amex's Card Sync technology to connect customers' Twitter accounts with their Amex accounts. Twitter users, mostly businesses, then tweeted out deals that could be redeemed right in Twitter's ecosystem, though you would actually have to go somewhere else to cash in the deal. The new program basically cuts out the extra step. If you've connected your Twitter account to your Amex account, you'll soon be able to buy an Amazon Kindle HD for $149, an Xbox 360 with accessories for $179, a $25 Amex gift card for $15 and a number of other products simply by tweeting a specific hashtag. Amex immediately sends a confirmation tweet to you that contains a confirmation hashtag, and once you do, Amex charges your card and sends you the product with free two-day shipping.

There are a couple of things to like about this new Twitter-commerce idea. The big one is that you can get good deals. The Amazon Kindle HD, for instance, retails for $199. If you buy it with a hashtag, though, you save $50. In effect, you get paid for tweeting. The scenario is even more obvious with the $25 Amex giftcard that costs just $15. The second thing — and we're already bending our will a bit here — is that it's arguably convenient. Surely you've been walking down the street and thought, "I'd really like to buy an Xbox right now, but if I start tapping my way around shopping sites on Internet, I'll surely step in a hole and break my big toe. Wouldn't it be easier if I could just tweet about my desire to spend money on this thing?" Yes, it would! It would also tell all of your followers that you are buying this thing which is a feature that you may or may not want, but it's one that makes Twitter and companies like Amex very excited.

At the end of the day, this new hashtag shopping idea is really just a more sophisticated form of advertising. Since Twitter's struggled a bit with its business model, it's very open to creative approaches. "We're convinced that commerce is going to be one of the areas (for which) advertisers are going to start using our platform," says Joel Lunenfeld, Twitter's vice president of global brand strategy. And if it wasn't already clear by the first sentence of this post, it should be by now: tweeting purchases is a social media marketing manager's dream come true. Not only are you engaging with the brand one-on-one, you're telling all your friends about it publicly, inviting them to engage, too! (Social media marketing managers love words like "engage.")

There are a lot of things about this arrangement not to like, but we'll leave it to our commenters to point them out. Suffice it to say that this strange new social shopping idea is both strange and new. It could fail fabulously, or people could be really into it. Kind of like Twitter, circa 2007.