It was Visa cards that funded many of the early assaults on the casinos and poker rooms of the 90s. Other forms of payment may since have come along to challenge this dominance, but credit cards remain a first choice for the casual player. Why? Well, quite simply, most of the people in the western world have access to a credit card. Many of us pay for the majority of our items this way, so it's an obvious choice. But it's not necessarily the best.
The most obvious advantage is convenience. Yet, e-Wallet accounts (particularly Neteller and Skrill/Moneybookers) are at least as easy to use once set up. And while the speed of Visa cards is similar to that of e-Wallet accounts when it comes to making deposits, the latter are much faster for deposits. You can certainly expect withdrawals to an e-Wallet account to take less than 24 hours, and the actually transaction will probably take a third of that time, if that. In contrast, it frequently takes 3-5 days for a credit card to receive a withdrawal.
Neither are credit cards particularly cheap. Whereas moving money to and from an e-Wallet is often free, credit cards are generally subject to a transaction fee. These aren't generally very large sums, but an extra 1.5-3% can make quite a dent to a three- or four-figure deposit. There's also the chance that you'll be hit by a 'cash advance fee'. These additional payments are frequently levied on gaming transactions. Again, these are small sums - £5 maybe - but if you're depositing a quick £20 or £30, an extra £5 charge on top of a 1.5% fee can be highly annoying. And, given that you're unlikely to see such fees when using an e-Wallet account, it's questionable whether you should be prepared to pay such additions at all.
Security is also an issue. If you have to send your full credit card details over the web every time you make a transaction, it's only a matter of time before somebody grabs your details. An e-Wallet account often has better methods of dealing with this sort of crime, and changing the details should be easier than having a completely new credit card.
So the savvy gamer will opt for e-Wallets over Visa, since the latter come with slower and more cumbersome withdrawal procedures, higher fees, plus a slight distaste when it comes to gaming sites - although Visa are far more accommodating here than Mastercard. Having said that, Visa cards are accepted everywhere, and money can be used on credit - although whether the latter is a plus or a minus will depend on how concerned you are about being pulled into a spiral of debt. Undoubtedly, Visa will remain a favoured option for many. But it's worth being aware of its faults.