Mobile ad budgets are headed up next year, according to a new study. Nearly one-third (31%) of ad agencies expect to spend between $100,000 and $250,000 on mobile advertising in 2010, compared to 22% a year ago.

Almost 13% plan to spend $250,000 to $500,000, up from 4% in 2009, and more than 15% will earmark more than $1 million for mobile campaigns, compared to 11% a year earlier. Nearly a quarter (23%) are budgeting less than $100,000 for mobile and 10% don't know how much they'll spend on mobile.

The study also found 60% of non-mobile marketers plan to buy mobile advertising in 2010.

The findings are based on a September DM2Events.com survey of 100 agencies by mobile ad network Millennial Media and DM2Events.com. They're not exactly disinterested parties, so take the results for whatever their worth.

Two-thirds (67%) rated mobile advertising as "somewhat valuable" and 30% said it had become an "indispensible" part of the media mix. Among agencies that have run mobile campaigns, 78% said they met campaign goals and 80% said they had developed internal resources to support mobile efforts.

The most common reason for campaigns falling short was a lack of reach, cited by 26% of those surveyed, followed by running the "wrong" creative (18%). Standardization of devices and ad units was the thing most agencies mentioned to improve mobile marketing. The growing proliferation of Google Android-based devices should help advertisers more easily run campaigns across different smartphones.

How is your mobile budget shaping up for next year?