Today I noticed a significant decrease in touch screen response.

Always install app updates,so can't remember correlation.no new hacks.might have been a cydia app update yesterday.

Rebooted.
Cleared safari cache...
Sbs settings free ram.


Ideas?

I had a similar problem, screen kind of jerky, slow to open apps. I did this; Try a soft-reset. Close all apps then - Hold down the HOME, bottom button, and the SLEEP, top button, for about 10 seconds until the Apple icon appears. Allow it to reboot, it may take a few minutes, don't panic like I did, wait for it to reboot. Cures many weird problems on iOS devices. One of the things we all should do, is keep a record of all the updates and new apps we install. And, one day, I'm going to do that, before it's to late, I hope.

Since you already said you rebooted I won't suggest you do that again

You might try uninstalling the latest apps you have installed or updated. Trial and error approach works well for uncovering these kinds of problems. Especially if you know specifically when the problem started.