I assumed that the cost to the city was mostly of the startup variety, namely installation and associated tasks. This would mean that in the future, it could be a revenue generator. But it turns out that it's running at a loss, annually. From the report itself:

2008: 2.3M revenue, 3.8M costs (1.5M loss) 2009: 3.0M revenue, 4M costs (1M loss)

The bulk of the cost is "vendor contract cost" which I believe means ongoing support, and appears to be on top of the initial investment.

It appears adding more cameras would only compound the losses.

(disclaimer: I do not read reports like this for a living; interpret my analysis at your own risk)