Although I use both, the problem with Moneybookers for me is the fact you must pre-fund your balance before you can purchase anything. If you use your credit card (CC) for pre-funding, there is a low limit that you can pre-fund on a monthly basis, so if I want to buy something on NP using a credit card and moneybookers that's larger than my Moneybookers monthly limit, I'm out of luck. Also your money has to sit in the Moneybookers account until you're ready to buy something. The other way is to do a bank wire, but that's a pain and there is still the issue of your money being tied up as a Moneybookers balance. Also, there are tons of fees on Moneybookers, like pre-funding your account, making payments, etc.
I like to float my cash with a CC and PayPal allows me to do that. If an NP thread says Moneybookers is my only option to pay on a domain, in most cases I must pass it up, even if I like the domain.