Google has just doubled the size of allowed attachments in GMail from 10 MB to 20 MB. Why you might ask? They have some ideas:
Now you can start sharing more of those home videos, large presentations and files you just can't seem to get smaller.
I happen to think that maybe you should think about making those files a bit smaller. Maybe you can send and receive a 10 MB file in GMail, but if your correspondent doesn't have the capacity to receive files of that size, then your files will be going nowhere and none too fast.