CompuServe Messages

I publish a couple of shareware programs (CheckItOut, a Quicken-Like personal finance management program) and (Stocks, a program to plot stock prices). I was wondering if people would be more likely to register for shareware if you could give your credit card number via e-mail or a phone call. Or is it that it doesnt matter, if you decide to register, you'll do it via regular mail. I am trying to decide whether to go for the expense of setting up a merchant account. Jim Bug Free Development