When compared to other marketing channels, email has the highest return on investment (ROI) and the lowest costs, one expert asserts.

Meenakshi Wali, the co-founder and business development head of promotional agency Rupiz Xpress, suggests that a number of online retailers are likely to increase their email marketing budgets, potentially at the cost of other online promotional strategies.

This is because the medium helps generate sales and build leads, she continued.

"A well-executed email marketing campaign can work wonders for a retailer, not only in terms of increasing revenue but also in terms of maximizing its online presence," the company stated.

Earlier this year, JupiterResearch forecast that the amount spent on email marketing will reach $2.1 billion by 2012, from the $1.2 billion spent in 2007.

However, David Daniels, vice-president and research director at the organization, stated that marketers must work hard to ensure email communications are relevant to recipients.

David Schatsky, president of JupiterResearch, stated that businesses must adopt best practices if they hope to succeed using email.