One of our colleagues uses a mac, he has both the mac and windows operating systems on it... nowonline.in works on safari... the only challenge that we have faced on safari is that you can't add scrips on the marketwatch...
The workaround is that you can save marketwatch on internet explorer using another system with all the scrips you trade and then trade using your ipad...
Also vmware has this product called fusion, this can be installed on your ipad and all the windows applications can be run through it...demo is available on their site...
Cheers...