I'm glad my Curve was up for being replaced when it was, because it just so happened to correspond with the launch of the Droid X. I've had a great couple of months tinkering with this phone and seeing it get rooted (twice), OC'd, custom ROM'ed, and all that good stuff. But I'll be completely honest with you... if I was in your shoes right now (that is, having a phone that's not up for an upgrade as yet, which means you'd have to take a hit to upgrade to something else), I think I would personally wait until the 1st of the year to see what the dual-core processor phones coming out look like. I certainly wasn't going to wait for 6 months for them, but at this point, I think instead of having to pay a penalty to get the best phone of 2010, I would probably wait to see what the first great phone of 2011 has in store for us. If nothing in January wow's you, you can always go ahead and pick up a DX then... probably for about $50 bucks by then, and without having to pay the penalty to do so.
Now then, for anyone who's contract is up right now and is looking for a phone, I would say you are probably safe going with a DX now... but if you're willing to wait, then it MAY pay off for you. I stress MAY because we have not yet seen what is coming out, so it's hard to say if they are worth waiting for or not. They might be absolutely insane, but then again they might be more along the lines of what is just now getting ready to be released. The new phones coming out really do nothing for me other than the Motorola Defy... not that it would talk me out of my DX, I just think the Gorilla Glass and element resistant nature of the phone are two steps in the right direction for smartphones. But if I were on the market for a phone right now, I would still choose the DX over any of the new offerings in a heartbeat.
I was really expecting to see at least a few really kick ass phones up for grabs when they announced the new releases, but the options were pretty underwhelming IMO. And that makes me wonder if the new phones coming out in early 2011 will be completely off the hook, or if they're saving the real show stoppers until next summer again. Perhaps the cellphone industry is going the way of Hollywood... hold on to all the Blockbusters until summer!