Recycling paper and cardboard is hard to argue with because it is so easy to see the advantages. We all know that trees consume CO2, and if what we hear about Global Warming is true, then recycling paper products could do nothing but good for the planet.
There has been some controversy about recycling plastics, in that the process is energy intensive, and the solvents used are more damaging to the environment than the plastic. It is important to consider that plastic is made from petroleum and we should make any effort possible to develop technology to move away from petroleum usage of any sort. However, there is some good news from North Carolina where researchers have found an efficient, one step process that allows plastic recycling to be achieved in an "environmentally benign procedure".
There is also a company named Terracycle that re-uses plastic drink bottles to package their organic "worm poop" fertilizer. This is a perfect way to re-use plastic, and has made this forward thinking company a very popular and respected player in the eco-friendly market.
As for glass recycling, it is a very tough issue to debate. The better solution would be to reuse any glass product that can be reused. Glass jars can be used to store leftovers as opposed to plastic tupperware containers...and will last far longer as well...not to mention that you can alleviate the worry of carcinogens like Dioxin leaching into your leftovers from the plastic containers.
Developments are also being made in creating new forms of transportation that could make local transport of these items less environmentally damaging. Solar powered vehicles and Hydrogen fuel cells become more of a reality every day.
So, yes...i think that recycling could potentially save the planet if we continue to look to newer, cleaner, more energy efficient methods of recycling or reusing.