A:AnswerI read in many comments That the bundles offered by other retailers do not come as pictured, the memory cards are often not brand name and often do not work at all.
A:AnswerMy 710 worked well in all conditions so I would expect my new (today) 730 to at least as good.;
just have extra (Canon, aftermarket no good.) battery for extreme cold & wind.
A:AnswerI was wondering the same thing, and found some comparison videos on YouTube. Here's one of them. Hope this helps answer some of your questions:
https://www.youtube.com/watch?v=vnuWaMUPS8E
You will also find video reviews of both of these models on YouTube.
You can also compare the differences between the PowerShot SX720 and the new SX730 here on Best Buy's website by clicking on the "Save For Later" options above the color choices of the SX720 and the SX730.