Does a lead singer make a band?

I am a guitarist, but 98% of the time, the singer Is what breaks the band (as No-Mercy says) but not necessarily makes it. Yes there are exceptions. Yngwie has had singer after singer, but has made most work fine.
Metal Church was an example I like as well. I actually like the Wayne era, but it pales in comparison to the Howe era.

I do have to disagree with the Skynyrd though. Though I love Blackfoot, I always just considered Skynyrd "ok." I don't think Johnny Van Zant is as good of a singer as Ronnie was, but with Medlocke (former Blackfoot vocalist/guitarist) now on guitar, LS is more heavy and I like their new song as much as any "classic" they have.

Bryant
 
On the flip side, when freddie mercury of queen died, queen would never be the same again. freddie mercury was queen. the band died with him.

Not really arguing your point on Freddie...of course he is one of the most unique and greatest singers ever and yes Queen would never be the same without him. But "the band died with him" may be a bit harsh? I think Freddie was surrounded by some pretty good talent especially in Brian May...a great player / writer. I think Brian was just as important to the bands success when the original line-up was functioning and in thier prime.