OS and sync

I have a MacBook Pro running 10.6.8. Got an iPad almost at its birth, but just bought an iPad 2 and gave 1st one to husband. iPad 2 is OS5, laptop is OS4. I synced once but Apple store staffer said I must upgrade to Lion on laptop for them to sync properly. True or not? What harm could have been or could be if I synced them again, even daily?

On iPad 2/OS5, the Music app that has replaced iPod has almost no user controls except volume -- no shuffle, no EQ ... or am I missing something??

Thanks in advance.