Electricity always takes the easiest route. Or the route of least resistance. How do you like that, electricity is lazy, I knew I liked it for a reason.
The electricity (lightning) hits the top most point of the car (roof) and travels through the skin, all around the car and exits through the tyres to earth.
As long as there is no high resistance or break in the circuit, and there is sufficient cross sectional area to carry the energy, then everything should be OK. The soft top hoops are metal and as long as they are successfully bonded to the chassis then they will act as a Faraday cage.
For all of you HCHDC, this may not apply as you were stupid enough to be driving around with your roof down.
It won't be as effective as a tintop, but it should still work.
James, your statement is not altogether true but it is nit picking. If the cars resistance is higher than yours, YOU will conduct. Or if the impedence of the Faraday cage (car) is not sufficient to disperse the energy safely, you could end up with a face full of lightning.
http://en.wikipedia.org/wiki/Faraday_cage
Faraday cages are normally used to shield Communications Equipment and delicate electronics. It can stop signals getting in, or out, so is used for security purposes as well.
Anybody want to drive to the Siemens test facility in Germany and try it out??