Okay here is my 2 bits (if that really means anything). I have looked alot at laptops for the last month or so. I see that Killernotebooks has made his point, which by the way seems to be very intelligent. I have looked at the E1705 notebook that you are asking about and it seems to be an interesting setup.
First, before I get side tracked, please google "Dell laptop coupons" before you buy the Dell laptop. It can save you upwards of $650 on at $1999 configured laptop, so don't buy directly until you use the coupon.
Second, from the information that I have read, the x1400 fits somewhere between at nVidia 6600 and an ATI x700 video card. If I understand it correctly, the x1400 has better (more up to date) rendering than the x700. I'm not sure if that is really a critical issue with your decision, but I thought that I would mention it.
Third, Yes the E1705 has the new Dual Core Intel chip, which might be important to you, but I'm not 100% it is better than the AMD Turion. You can probably find hype more from the Intel side than you will from the AMD side.
I personally think that if your going to buy today or shortly, you might want to look at the 64bit capability of the AMD Turion. You might not think it is a major deal breaker right now, but if in 6-12 months from now, you end up wanting to install the new Windows Vista program you might think twice at what you bought. This might not be an issue for you, but I thought that you might want to consider this when making you decision.
I also think that Intel is waiting to release the 64bit version of the Dual Core until Windows Vista is released. I know that Microsoft and Intel work together closely and try and time each others releases, so each one benefits themselves. If I were a betting man, Intel release the Duo Core (32bit), because they were getting beat up from the AMD (64bit) side for some time.
I normally don't feel compelled enough to logon and register to voice (type) my opinion, but these types of subjects seem to make me do it. And trust me when I say there is ALOT of Intel hype concerning there new chips (I work with alot of people that believe the hype). Don't get me wrong though, the latest Intel chip is an improvement over the previous one.
So hopefully my 2 bits will help you in your decision. I know that I'm currently looking for an affordable laptop ($900-$1,100) that I can play the latest games on (I know, that is almost impossible to do on that budget).
One last thing, Killer knows what he's talking about when it comes to the upgrade costs for the Dell's. If you can at all possible, order the minimum amount of ram/hard drive, that you can and install your own RAM or Hard drive. Please use the 7400rpm units if at all possible, it will improve your playing speed. By installing the upgrades yourself, you will save you a bundle. If you don't like to do those things or are not comfortable doing it, then by all means just order what you want. If you have any doubts, you can use this forum to hopefully straighten you thoughts alittle.
I hope that you will feel more informed and can make a more intelligent decision.