I've never really been up to date on shredder technologies because I never put much thought into them. To me shredders were that plastic box that you put sensitive papers into that have all the silly pictographic warnings about not putting paper clips or your tie into it. Fortunately, one of my co-workers told me that those warnings aren't just a joke, they can cause serious injuries. It might be funny to watch a business man get his tie caught in a shredder but most business people have good enough reflexes and are strong enough to stop anything except some minor tie damage.
Most major shredder related injuries come from young children or animals who can't really comprehend what the shredder is for or what damage it can do. It isn't hard to find reports of various shredder injuries when you browse the web and you can find some pretty harrowing photos if you want (I won't spoil your lunch), but there are few places that offer much for a solution. Everybody says the only way to keep a shredder safely in your home is keep it unplugged when not in use. You can turn it off, but if there is a finger, tail, or tongue that can get caught in it, those body parts are connected to others that could find a way to turn the shredder on.
I can't tell you that buying a new shredder will allow you to safely keep your shredder plugged in while children and pets run amok, but I can tell you that the latest shredders from Fellowes have some impressive safety features that might put your mind at ease. The primary safety feature in these shredders is the patent pending SafeSense override that stops shredding when fingers get close to the shredding input port. We have a Fellowes PS-79Ci Shredder in our office that has the SafeSense feature. Even thought I wasn't allowed to get out my tools to find out exactly how it worked I was able to do some testing and it seems as if the chrome trim around the shredder input has a capacitive sensor that shuts off the shredder. The Fellowes advertising tells you it will shut down your shredder if your fingers get to close which sounds like it might have been a proximity sensor, but at least on our shredder you need to make physical contact with a sensor to trigger the SafeSense feature.
The capacitive sensor on the shredder we have works well enough to keep an adults finger out of the shredding mechanism, but if a child had small enough fingers they could slip between the sensors. Something as large and slobbery as a dog's tongue would easily trip the sensor, but a cat's tail may or may not trigger the sensor (I am not going to test it). I can't say for sure that all SafeSense enabled shredders use only capacitive sensors, but looking at a Commercial Grade Shredder with Fellowes SafeSense I can't see anything that sticks out as a capacitive sensor, so it might have a more sensitive system to keep fingers out.
Unfortunately, even though shredder technology is advancing rapidly, the current crop of shredders isn't going to be a fool-proof accident-proof replacement for your current shredder. You should still unplug them if they are not in use, and at the very least turn off the auto-on feature to avoid accidents. If problems arise from Shredder of Teenage Mutant Ninja Turtles fame and not a common office paper shredder, I'm sorry, I can't help there.