The Software Center in 11.10 is much slower than it was in Natty, and on my five years old machine it often becomes unresponsive. What can I do to make it run faster?
Upgrading to 12.04 would be a good idea (it wasn't available when you asked the question originally).
After 11.10 was released, the developers acknowledged the Software Centre was starting up a lot slower than it had previously. Startup time of the Software Centre was significantly improved, ready for the 12.04 release.
Of course startup time is only part of the overall story, but I think it would be worth you trying.
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