Online ad spending is set to grow almost 14 percent, from $45.6 billion, in 2010, to $51.9 billion, in 2011, according to a new forecast from Borrell Associates.

By next year, local online advertising should grow by almost 18%, from $13.7 billion, in 2010, to $16.1 billion, in 2011.

Targeted display advertising is forecast to grow almost 60 percent in 2011, reaching $10.9 billion for national and local combined. While national advertisers will increase their use of targeted display by nearly 50 percent, local advertisers will out perform that. Use of targeted display by advertisers local to the markets where their ads run will more than double, reaching more than $2.3 billion next year.

Borrell expects national paid search ad format will see a double-digit spending decline next year, moving down 11.3 percent. The drop will be caused by lower pricing and churn, but will be lessened by a local advertiser increase of more than 10 percent.

Email advertising will see moderately strong growth in 2011, up 9% to $16.0 billion for national and local. Growth in this format is almost all from national advertisers; only 3% is local.

The streaming video format is forecast to continue to its strong growth, increasing more than 60 percent to $5.6 billion next year. Two out of every five streaming video ad dollars will come from local advertisers next year.

Online promotions will top $24 billion next year, up 10% from this year's totals. Much of this increase will be due to the rising use of online couponing, forecast to grow almost 14%, to $9.1 billion, in 2011.

Mobile marketing continues to grow, driven by apps, user-friendly browsers and 3G/4G speeds.