Gavin Andersen proposes to increase the maximum bitcoin blocksize.

If we increased the maximum block size to 20 megabytes tomorrow, and every single miner decided to start creating 20MB blocks and there was a sudden increase in the number of transactions on the network to fill up those blocks….

He tells:

CPU and memory usage scaled up nicely, there were no surprises. Both CPU and memory usage for the 20MB blockchain were within my criteria of “somebody running a decent personal computer on a pretty good home network connection should be able to run a full node.”

Increasing the maximum block size has an impact on the block chain. While running a full bitcoin node is memory extensive, this could indicate an even faster growth of disk space required for the block chain. If the block size became 20MB tomorrow then it might still be four years before the first 20MB block occurs, and five years before they are common.

Interesting reads on this topic:
https://blog.bitcoinfoundation.org/blocksize-economics/
http://gavintech.blogspot.nl/2015/01/twenty-megabytes-testing-results.html