This sounds much like the upgrade that I was planning for myself (3200+ and a GB of DDR400) until I realized that I don't do anything with this machine that warrants it. But if you have the money...

The actual jump in clock speed isn't very much (1.73GHz -> 2.2GHz). But there is also the front side bus speed, too. A jump from 266MHz to 400MHz, especially if you pick up a pair of DDR400 sticks along with the CPU, will certainly make a difference.

Will it be noticeably faster? I think so. But whether or not you will be happy with that can only be determined after you purchase it or decide to wait for something better to come along.

It's a trade-off I deal with all the time - desire versus impatience.