"Worth" is very subjective to what you do and your finances.
OTOH, the new Haswell MBP's are around the corner. So, unless your existing machine is dead and you need one right away, it may be 'worth' it to wait a few weeks and see what Apple comes up with.
it might be faster, but then your MBP is nowhere slow enough probably for what you want to do - so save your money and dont buy one is my suggestion. figure out something else to do with the money.
What are you using your 2011 for? I think with a RAM and SSD upgrade, a 2011 machine is plenty fast to handle today's task. If you are looking for a better display, then go for the upgrade.
Thanks everyone. I don't HAVE to get a new one. I was going to give this one to my son. I'll check out the SSD. Is there someplace good to purchase one? Only thing I have done to this one is upgraded the RAM