Lack of moving parts is great, but flash allows a finite number of write cycles.
Some people over on xtremesystems have done Endurance testing, and the 64 GB m4 took over 700TB of writing to for failure to occur, and 172 TB to reduce the MWI to 0.
In a little over a year I have only written 4.1TB to my SSD in my desktop. Write cycles are very unlikely to run out for me before I replace the drive.
http://www.xtremesystems.org/forums/showthread.php?271063-SS...
I think Intel released some information on the reliability of their SSDs a few years ago but that was likely because they knew they were doing best and their enterprise customers are very interested in that for their data-centre rollouts.
The very limited information I've seen suggests to me that a few years ago SSDs had a much higher failure rate than HDDs (double in the first 6 months) but that has been falling very quickly with each new generation of SSDs (and as the profit margin grows and manufacturers have to work on reputation to justify the markup).