Surely someone has come up with a spreadsheet or calculator to run comparisons?
In Canada there is:
Even after the initial comparisons you may still need to dig deeper to understand the rules and reward criteria. The information provided by the card carrier does not always allow you to do a similar comparison of the value of the rewards points. I find that I still need to create my own spreadsheet to calculate how much a point is worth before I can take into account the other factors (type of reward I want, spending habits, annual fees, etc.).
http://www.cardweb.com/ and http://www.bankrate.com/credit-cards.aspx are both good sites to see what is available. However comparing them isn't a simple task because the best card for you depends what you desire most.
I do a very simple math equation though when I am comparing bonuses: which has the biggest cash back reward?
I can use cash to buy airline miles, products at the store and gift certificates. I can use cash now and in the future, I can pay bills and give it as gifts. There is no other reward that can fill all of those shoes.
If I buy an airline ticket, I get cash back regardless of the miles. If I shop at the grocery store, gas station, movie tickets or anywhere else, same deal. No other reward is as flexible.
I will fully admit there are special circumstances where you are best served by a specialty reward, but I would call those rare in my travels. If the credit card company is offering the deal it has to be good for them, and since they offer rewards and point more than cash back, I have to assume rewards and point is better for them than for me.