I think it's matter of choice there are exploits in every browser you use but the only thing you can do is to educate yourself about these exploits and then find ways you can protect yourself from these exploits as it is time consuming process
as software companies will know about an exploit and then redevelop their program accordingly and in the mean time there would be another exploit undercovered
yes,i agree with you ,i think the IE 7.0 is very good,it's better than the IE 6.0.i like to use it on my computer now.it works very good,i can't find it makes the mistake.