In the near future I'll be purchasing a new laptop, and I'm wondering if I should get a SSD or not? Here's what I'm thinking would be the ultimate setup, but I'm not an expert with this stuff by any stretch. I'm thinking a Dell Precision M6400 Covet with a smaller (128 Gb SSD) and a larger (320 Gb) 7200 RPM normal HDD. I was thinking I could put the Operating System and programs and stuff all on the SSD for improved load time, and store all my data on the normal hard drive where there's more room.
Is this a good idea? Will it make a noticable difference?
It will make a difference! If you can afford the price get one.
Compared to a classic HDD, SSD drives:
Right now, July 2009... I would say no...
The reliability of the SSD is not entirely there yet. Most are warranted for a year, and have a hard limit on the number of times  they can be written to. Until that limit crosses 100,000 I personally don't have faith to recommend this technology.
That said, companies are working to break through and extend the life of the flash memory.
For the current price point, I can't recommend them
I just re-read the content of the question. Yes, I would get a laptop in the configuration you are discussing. With a secondary drive, I think you are in a lower risk configuration that I could endorse. http://en.wikipedia.org/wiki/Solid%5Fstate%5Fdrive#Disadvantages
Be careful, not all SSDs are what you think they are.
For example some netbooks are sold with so called "Solid State Drives" however they actually just have what amounts to a USB flash/key drive soldered to their motherboards.
This means they have ok read performance but write performance is pretty awful. This is why so many netbook owners have felt the need to upgrade to a "proper" SSD.
So when buying, the question to ask is: Can I remove the SSD and replace it with a standard Sata / IDE drive if needed? If the answer is yes then you know are getting a decent SSD.
This is what you'll get with a SSD.
There will definitely be a noticeable difference.
What should you be concerned about with an SSD?
There's a limited lifespan on the drives because of the fact that the cells can only be written to a number of times. So your drive will eventually fail. However, the lifespan I believe has been calculated to be about the same as a regular HDD.
I'm using a Dell Mini 9 with an upgraded RunCore 64 GB SSD. It's the fastest netbook or notebook I've ever used (in terms of booting time and app launch times at least). The boot up time is nothing short of amazing. 15 secs from cold start to desktop.
Joel Spolsky has a good review of the Intel SSD at : Solid State Disks  His rejuvenated ThinkPad experience is similar to what I experience daily on the Mini 9.
AnandTech also has an article on SSDs, Intel Delivers One of the World's Fastest Drives 
My two cents? If you can afford it, go for SSD. It's the future. It'll be the best upgrade you can do to achieve super fast boot time and app launches. Web browsers, IE8 and Safari (Windows) loads pages demonstrably faster probably because they can access cached files real fast quick due to the high read speeds of the SDDs. http://www.joelonsoftware.com/items/2009/03/27.html
For a laptop, definitely. Besides loading faster, you should also notice longer battery life.
WIll this make it easier for you:
Intel has announced two new solid state disk drives made on its leading-edge 34nm process. The two new SSDs are X25M SATA parts weighing in at 80GB and 160GB, and they're meant to replace Intel's existing X25M drives in those capacities, but at 60 percent less cost and with better performance. The 80GB X25-M is $225 in lots of 1,000 (down from $595), and the 160GB is $440 (from $945).
Big price cut and slightly better performance on the Intel SSD drives
Yes it will make a noticeable difference. I recently had the pleasure of ordering a new laptop and purchased a SSD. Windows boot time is under 30 sec and a compile time that used to take > 6 minutes is now down to 1 minute or less.
If you have the money to purchase one, do it. Just make sure you don't get a lemon. I really recommend reading this article - The SSD Anthology: Understanding SSDs and New Drives from OCZ  - to inform you further of the pros/cons of SSDs. http://www.anandtech.com/printarticle.aspx?i=3531
If you are going to wait with this, I would recommend an SSD, yes.
However, if this is something you're going to go with in the near future, going with a VelociRaptor instead (10000 rpm) will be cheaper per GB, yet a significant difference from a normal 7200 RPM disk.
Plan ahead, remember, the SSD disk are only now becoming common, just as the prices are starting to get better as time goes on.
Yes, a good SSD will make a dramatic difference in disk speed. It sounds like you're going all-out on the laptop anyway, might as well get an SSD, too.
Most (maybe all) SSD's have a hard (small) limit on the number of writes. Any hard drive that has this small limitation in my opinion is not quite ready for use. At the end of the day, the primary purpose of a hard drive is to store/retrieve data. Battery life and quietness is cool but if it has limitations on storage, what is the point?