Both will do whatever you ask adequately. Some say DP has a better graphical interface and is better for the composer, but worse for the engineer-type and mixing. I wouldn't know personally, as I use Logic. All I can say is that Logic has never let me down, but there have been times when I had to jump through hoops to do something that should have been straight forward. And there's a steep learning curve (but there are plenty of great resources, like http://groups.yahoo.com/group/logic-users/ and http://logicfaq.omega-art.com)

I personally love Logic, and wouldn't consider switching unless it wasn't developed anymore.

And..... (dun dun dun dahhhhhhh) Apple has just announced Logic Pro 6 today!!!! (see the thread for details.

What that means to you is that the initial investment for Logic ($999 MSRP) just got a little more expensive, but you get a whole lot more than you would for the old (~$699 retail) price. Because you get Logic and all Emagic's optional plugins. What a deal. And Logic Pro may still be cheaper via retail outlets. If I were you, I'd hustle out to your nearest audio dealer and buy Logic (Platinum or Gold version 6). The upgrade from Logic Platinum and Gold to Logic Pro is only $199. So you'll save yourself $150 or so.

Of course you can go for Logic Express (or Logic Big Box - same thing) for $299 or cheaper in retail outlets. I'm not familiar with DP pricing structure.

there are other options, like Cubase/Nuendo, ProTools LE, and a host of less expensive alternatives, some of which get rave reviews. You'll have to do a bit of comparison shopping, but they all basically do the same thing in their own way.

Basically the only way (besides OMF, which is supposedly an exchange format for sequencers -but I've never tried it) to transfer songs between sequencers is to export each track as audio and import each track into the other. Laborious, but it works.

here's that Logic FAQ link again, the parenthesis messed it up.

http://logicfaq.omega-art.com