For some good escapist reading, this book certainly does the trick. It's fast-paced, funny at times, with a few excellent sub-plots. The characters could use a little more fleshing out, and at times their movements seem chronologically implausible, but if you can suspend your disbelief for the few hours it will take you to read it, you probably won't notice.
As for the plot itself, Rubenfeld takes as his jumping-off point the still-unsolved 16 September 1920 Wall Street bombing, and creates a fictional scenario to explain the attack which involves a whole series of conspiracies leading up to the highest levels of finance and government (along with oil money, international terrorism, and warmongering based on forged documents). It comes across as a bit heavy-handed, to be honest - but nonetheless, I enjoyed the book, and recommend it for a nice long winter afternoon's entertainment.
