Swissballs have been used for years and have most recently become popular in physiotherapy and strength and conditioning programs.
As with all training methods there are debates both for and against.
The benefits have been shown to include improving strength, endurance and flexibility to prevent back injury and low back pain.
Numerous studies have shown a link between low back pain with weak trunk muscle strength and a sedentary lifestyle.
Improving and changing these two factors can go a long way to releasing that lower back pain.
A program of just 45 minutes, 3 days a week for 8 weeks will be enough to show improvements in strength, flexibility and endurance in a normally sedentary individual.
With 2- 3 sets of 10- 15 reps.
Common exercises in a program like this would include:

• Swissball (SB) Wall Squat - Ball against the wall with back against ball and squatting down
• SB Shoulder Bridge - Lying on ground with heels and lower calves on ball.
  Then raise hips up until there is a straight line from feet to shoulders
• SB Alternate arm and leg extension - Lie on top of the ball with stomach over the ball.
  While balancing on fingers and toes raise the left arm and right leg, then alternate
• SB straight arm crunch - Lower back on ball with feet flat on the floor shoulder width apart.
  Stretch arms back behind ball then come forward
• SB Back extension - Lie on top of ball in a position similar to arm and leg extension.
  Slowly walk feet back and hands out until your in a straight line
• SB Hamstring curl - Lie supine on the floor with heels and lower calves on the ball.
  Raise hips until your in a straight line then use your feet to pull the ball in towards you
• SB Leg raise - Ly supine on floor with ball held between the legs.
  Raise ball up to straight above your hips and back down without your feet touching the ground

Just type these exercises into YouTube to see how there done.
These exercises can be modified depending on ability and can be incorporated into another program or on their own.