SSD, is it worth it?

Well they are really the best hard drives that is currently in the market. But because not a lot of hard disk makers make them the price is still a little big higher. My advice is to wait maybe 1-2 years then maybe it will be the same or cheaper than the old hard drives.

definatly.. I invested in an ocz vertex 3 120gb for my main pc as the operating system drive. Performance wise, boot time is 8 seconds for my comp to load up windows 7. So going to have to get a couple more ssd for my data.

SSDs are a reliable solution as for them replacing HDDs I don't think they will do that as well for some things having a Disk might have an advantage like for servers and other things also the cost of SSDs are slowing the adaption of them. Now SSDs have a massive advantage over disk drives one of them being the need to not have to defrag the computer as well you don't lose anything by having the files every where as the computer can just find the file and load it with out having to spin up the disk and find the file that you want to load. (Actually read that it is bad to Defrag and SSD not sure if that is 100% accurate) Also as companies start making Motherboards and other computer parts for SSDs you might even get one that has no cable between the motherboard and the SSD which increases the speed because the SSD feeds the data right to the Motherboard no cable that in most cases actually goes slower than the SSD can push the data out where this case you will lose no performance boost from the SSDs speed. The Mac Pro by Apple has this feature for both SSDs and HDDs that you might have in it their are no cables to deal with which improves its performance. So I would say SSDs are worth it if you really care about performance and want a ton of speed of programs and your OS booting almost instantly.