My two cents for the tech heads... I upgraded my MacBook Pro to an Intel X-25MG2 160 GB SSD and replaced the DVD drive with a Toshiba 1 TB 5200 RPM HDD. I use the HDD for storing large files (SLR RAWs, videos, app images, etc) and everything else on the SSD.
Here are a couple of screen shots of my Activity Monitor taken when I was defragging my virtual machine disk image to recover some disk space. Sequential reads: over 200 MB/sec. Input/output operations per second (IOPS): often in the thousands, exceeds 10000 when installing apps. My previous 7200 RPM laptop HDD was lucky to hit 60 MB/sec and 120 IOPS for random reads/writes... my SSD is often 30 to 100 times faster!
The best part of all is the scalability. Loading Photoshop CS5 on its own takes about 3 or 4 seconds. Loading Photoshop, Lightroom, Word, Excel, and PowerPoint simultaneously takes a bit over 5 seconds. Amazing... especially in a laptop!
The current generation drives are literally twice as fast (or more) than mine
(Word of warning if you're planning on buying one... be sure to do your research, as the cheapest/slowest SSDs are virtually no faster than HDDs!)
My SSD was literally the single most impressive upgrade I've experienced in my 20 odd years of using computers at home.