I think I gonna spend some time looking at relevant rumors, but at least we can discard the Ageira and DSE official statements concerning Jump Holes as propaganda from corporations that decided to play god and artifically create the ways through space - and paid for that at least once in Texas.
Well, Jump Holes in Freelacer are the copy of the ones in Privateer and Wing Commander, as well as imitating the warp drive from Starlancer most probably, so we can assume that they are that dangerous.
In other words, modern navigation technology nullifies the risks of travelling through them, I'd say, though, they are still gorgeous and terrifying.