Actually you've both made good points.
But I have examined IBM's programming tutorials for maximizing the potential of the SPEs and I'd still say it resembles a juggling act.
And trying to compare a Cell to a standard PPC becomes difficult as the efficient use/programming of the SPEs is essential to harnessing the Cell's potential.
At least with GPUs there are some programming tools/standards.
Are there any software tools to help code for and manage Cell use?