[devinj]

No, not at all. Requiring an increase of 2048 bits over 14 years implies that computing power increases by a factor of 216 every year.

[beagle3]

That would be true if RSA keys were brute forced, but they aren't - e.g. 512 bit RSA takes days/weeks to break on commodity hardware these days, whereas 512 bit brute force (as is essentially needed for ECC these days) takes significantly longer than the estimated age of the universe.

See http://en.wikipedia.org/wiki/Integer_factorization_records

[dunham]

You need to factor in speedups due to advances in factoring algorithms, too. And it's possible that the software doesn't have any options between 2048 and 4096. (I have no idea, I didn't check.)