ATA serial HD and solid state HD – what’s the difference?

I'm considering to buy the new macbook pro 13-inch
cause I want to work on Final Cut express on it

but what is the difference between the 500GB Serial ATA Drive @ 5400 rpm and the 256GB solid-state drive? (ie which is better?)

I'll side with Andy.
However I have 2 slight differences.
First you can edit video successfully with a 13" machine.
If you have the bucks to get a 15", well then certainly do that but if not, then the 13" will do the job.
Second, get a 7200rpm internal hard disc. Don't need to get the biggest because you MUST have an external drive.
Apart from the security (backup) aspect, video consumes an enormous amount of space and if you are doing a lot then you will fill your 500GB drive.
External drives are not that expensive, (Seagate, WD etc)
Look for a 1TB drive connecting to your firewire 800 port and store all your video events on that drive.
Regards, Zyfert
the solid state drive is a bit faster, but a lot more expensive and much smaller in size.
the Serial ATA harddrive is a traditional harddrive with spinning platters and a read/write head. a solid state drive is like a big flash drive as it has no moving parts. solid state is much faster than serial ata and less likely to fail on you, however, since it is new, it is also much more expensive.
Solid-state drives aren't good enough to be worth it yet, IMO.

They have limited read/write cycles (Ie. after 2,000,000 writes it will slow/break). And while this has some of an advantage over hard drives (ie. you shake it, it doesn't break), it's hard to tell which is the best for you, time, or sturdiness.

Also, per GB, they're more expensive (newer technology), but in most cases they ARE faster.

Personally, I'd go with a desktop PC for video editing. You can build it to spec, know it inside and out, for cheaper. Many, many, many people edit on Windows. You don't need a mac to render video, JSYK.

Still your choice.
The solid state is better since it has no moving parts(vibrations don't matter) and it will have a much faster transfer(read/write) rate then the other harddrive. The 500GB SATA hard drive has platters inside that spin at 5400 RPM which is slower than desktop drives (7200-15000RPM). The slower a harddrive spins the less power it uses, but that also means that you can't read/write data from/to it as quickly either. These drives also have to be defragmented to keep performance at its best. Solid state drives can read and write anywhere on the disk at the same speed since they have no moving parts, removing the need to defragment the hard drive. Solid states can be slightly more energy efficient as well since they don't have to move anything, ever.
First up, don't listen to someone who doesn't own a Mac, and try seek advice from someone who's used a Mac for digital video editing, and even better all of that WITH a solid state disk.

I'm going to ignore the technical differences (I'm well versed so email me from my profile if you need to) and tell you about some of the real world differences.

You really should subscribe to the podcast called MacBreak Weekly. They discuss Mac hardware and software, and two or three of the guys on the "show" are very well into real world video work.

Leo Laporte is the host, and has a variety of Mac hardware, and very recently someone recommended he put a solid state disk into a MacBook (Pro?). It boots twice as fast, the battery life is better, it's much more resistant to bumps that a regular spinning HDD, and re-encoding video is approx twice as fast.

Don't get a MacBook Pro 13, you want the 15. It has a faster GPU, and that does make a difference in digital video work. (Especially when Snow Leopard releases in September this year for $29 upgrade fee)

The downside to a solid state disk is, they have smaller capacity (use an external Firewire 800 disk for archiving big projects) and they're so much more expensive.

Also ignore what you hear about defragmentation on drives. It's genuinely not a problem with Apple OS X on an OS X formatted drive.

I would choose a MacBook Pro 15, with a 7200rpm (spinning) drive just now. I would wait until solid state drives become cheaper and higher capacities (it's absolutely inevitable) and then I'd swap the drives. This is so easy to do, because the Mac is very good with backups and restores of your system.

And lastly, PCs may seem initially cheaper, but they are not good value at all. You have to buy so much extra (anti virus is only the first thing on the list, don't forget iLife and the strong integration of multimedia into the OS).
but the macbook pro i have it. and look how fast i can respond to your questions;