I've been running creative and industrial business start-ups for many years. I started my largest venture in a recession (1991), and went through the 2001-03 downturn after the dot-com collapse. The current one is much worse, bringing the world financial system to its knees, mostly for being idiots.
Recessions are like natural selection. They cull the weak, dumb and greedy, and prepare the landscape for an economic revival that will soon see people being foolish with other people's money. It's a shame that a man with President Obama's talents will have to waste energy "doing something" about the economy, though shoring up the banking system is not without merit.
For many people doing webcomics, a recession is a new experience, and I've been asking around to learn if anyone is noticing falling sales of merchandise. Ad revenue has taken a hit for many, but most can survive if they have an established merchandise business.
Conventions seem unlikely to do great business in the current climate, especially since for many cartoonists, breaking even is a smashing success, after paying for travel, lodging and food. With the convention season starting in a few weeks in New York City, cartoonist blogs seem quiet on the topic.
There are occasional exceptions, such as the famously broke cartoonist who obviously hasn't got the cash and is playing Twitter Hamlet, agonizing about whether she wants to attend. I feel empathy for any person struggling to get by, but the image management is an insult to her audience's intelligence. Building a career through fakery rather than good old work ethic = fail.
Maybe if she was less passive about developing her business, she'd have the funds. I mention this partly out of morbid fascination, but it's also a lesson: webcomic economics require high levels of passion in both comic creation and running a business. People who expect others to do things for them are usually lazy, and lackluster at execution.
So there is a lesson in what not to do. It's obviously essential to pour your energy into your comic and making it as irresistible as you can. You should monitor sales trends closely, and weigh the value of reducing, or increasing, the size of your orders from suppliers. They may be pinched, and offer incentives for larger orders that won't break you if they take three years to sell. In general, hanging onto cash is safer, though you can help the recovery by buying something once in a while, like a Hummer or some skyscrapers mortgaged above their sale value.
"Recession" is a bummer word, so resist having "Recession-Buster" sales events, unless you are selling living room furniture. Consider letting the prices do the talking: Lower them, and see what happens.
Get an incredibly unreliable traffic report free at Quantcast.com. Crumple it up, throw it away (but keep your monitor, silly), and turn to the demographics page. Are your readers lower income, young, and disproportionately male (PVP)? Much more likely to be Asian or Hispanic than most webcomics (A Softer World)? More likely to have children (Dinosaur Comics)? Unusually more female (Dresden Codak)? (Go Aaron!) Mostly adult/older adult (Something Positive)?
I concede there is no way to know the quality of Quantcast demographics except by testing known sites and comparing, which is hard to arrange. My feeling is that their numbers are useful, if you don't over-rely on them.
Each of those distinguishing demographics above is a marketing opportunity. For example, if Dresden Codak doesn't offer women's t-shirts, it may be a mistake. A comic with a lot of grade school readers, like PVP, might benefit from printing on shirts from American Apparel, which are designed to fit a younger body type and are even considered a selling point to some. A Softer World can find sites with similar demographics and see what they're selling. (These titles may already be doing these things. I mean this as a case study, not an analysis.)
At my past ventures, we didn't look much beyond monthly sales, until business slowed. Then we became fiends for any data we could use to target groups and spend efficiently. We never laid off an employee due to a recession.