From IRS.GOV:
Is it a Business or a Hobby?
It is generally accepted that people prefer to make a living doing something they like. A hobby is an activity for which you do not expect to make a profit. If you do not carry on your business or investment activity to make a profit, you cannot use a loss from the activity to offset other income. Activities you do as a hobby, or mainly for sport or recreation, are often not entered into for profit.
The limit on not-for-profit losses applies to individuals, partnerships, estates trusts, and S corporations. For additional information on these entities, refer to business structures. It does not apply to corporations other than S corporations.
In determining whether you are carrying on an activity for profit, all the facts are taken into account. No one factor alone is decisive. Among the factors to consider are whether:
You carry on the activity in a business-like manner, Yes
The time and effort you put into the activity indicate you intend to make it profitable, Yes
You depend on income from the activity for your livelihood, No
Your losses are due to circumstances beyond your control (or are normal in the start-up phase of your type of business), Yes, I don't get paid enough
You change your methods of operation in an attempt to improve profitability,Yes
You, or your advisors, have the knowledge needed to carry on the activity as a successful business, Yes
You were successful in making a profit in similar activities in the past, No
The activity makes a profit in some years, and the amount of profit it makes, and No
You can expect to make a future profit from the appreciation of the assets used in the activity. I sound better every day!
Bottom line: It's debatable.
Pros of treating it as a business:
Save $150/year
Don't get audited because I got 1099's
Pros of not treating it as a business:
Don't get audited because IRS says: hobby
Don't have to keep track of income/expenses/mileage