If you had the development chops along with the time and money, I'm sure you could make the cell very quick for certain needs (scientific, specific video encoding, etc).
However, a lot of third-party game developers have complained about it over the years.
"Anyone making a game, if you're going to make it for both, just lead on the PS3 because if it works on the PS3, it'll work on 360," he said. "We had to play catch-up on the PS3 because of the memory constraints and how it renders; how it processes is just different. And it's harder on the PS3."
And the best quote ever:
"We don't provide the 'easy to program for' console that (developers) want, because 'easy to program for' means that anybody will be able to take advantage of pretty much what the hardware can do, so then the question is, what do you do for the rest of the nine-and-a-half years?" explained Hirai."
http://news.cnet.com/sony-ps3-is-hard-to-develop-for-on-purpose/
Even Apple looked into the Cell, but ultimately Jobs said it was crap for general computing.
"Mr. Kutaragi tried to interest Mr. Jobs in adopting the Cell chip, which is being developed by I.B.M. for use in the coming PlayStation 3, in exchange for access to certain Sony technologies. Mr. Jobs rejected the idea, telling Mr. Kutaragi that he was disappointed with the Cell design, which he believes will be even less effective than the PowerPC."
http://www.nytimes.com/2005/06/11/technology/11apple.html?_r=1&oref=login
At NAB, a company announced that they will introducing an h.264 video encoder for professionals that runs proprietary software on the PS3.
http://www.techshowwire.com/2009/04...ion-3-at-broadcast-international’s-nab-booth/