eCPM: publisher's most valuable figure?

[sallam]

Greetings

While examining my stats in the last 9 months, I came to a conclusion that eCPM, if I'm right, is the most valuable figure for a publisher to watch.
I used to think that CTR is the most important factor. But in the long run, its your eCPM that tells a publisher how good he /she is doing. Its your sign for future potentials. CTR can be highly unpredictable. One day its high, and the next is not. It sure is an important factor. But its eCPM that realy gives you a look to your future.

Am I right in my conclusion?
Is it affected by the smart pricing system that google use to determine our cost per click?

[lammert]

The most important figure to watch is earnings per month. This is the product of page impressions and eCPM.