Currently Being ModeratedMay 2, 2013 8:45 PM (in response to M.A)
Updates normally list the main issues but they also often address other smaller issues too. Some of these might be security issues which are also worth addressing. I would therefore recommend updating but, if you unhappy to do so, then don't. However, sooner or later, you will probably have to update.
Currently Being ModeratedMay 2, 2013 8:49 PM (in response to M.A)
Rotary dial land line telephones probably work just fine these days as well.
Updates serve as steppingstones to the future. Eventually, refusing to update means you miss out on related technologies (e.g., apps) that assume the update is in place.
I have found over the years that Apple updates are extremely reliable. I have typically updated the day the updates are available, and never regretted doing so.