Should I get a Solid State Drive?
What are the advantages of a SSD drive in my laptop if they have not that a great lifespan and are quite expensive in first place?
Increased speed (especially when loading lots of small files on demand), higher mechanical durability/reliability and reduced power consumption are probably the biggest.
Wikipedia has a great article that further explains the benefits versus the disadvantages:
http://en.wikipedia.org/wiki/Solid-state_drive (about half way down)
SSD drives are extremely fast compared to normal drives they have no moving parts so they are not susceptible to the mechanical issues normal drives have.
This makes them great for laptops as they are slower to begin with and need any edge they can get and because they have no moving parts they are less likely to break if you drop the laptop.