A coordinated effort by global central banks, led by the U.S. and the Federal Reserve Board’s 0.5% emergency rate cut today has more or less calmed the financial markets this morning (down about 100 points in mid-morning trading).

I say “more or less’ because who really knows? But the economists I’m seeing and reading think that lower rates will get more people back into big ticket items like houses, cars and travel packages – a must for an economy that is being dragged down by frightened consumers. Plus, the rate cut relieves pressure on banks who either can’t or won’t find people and businesses to lend money to. The rate cut should help in that area (it historically has normally done so) but as I’ve been saying, we are not in ordinary times anymore.

The economy is also taking a toll on mobile phone sales, with UBS telecom analyst Maynard Um telling Reuters that his mobile phone growth forecast of six percent, made earlier this year, is being sliced in half to three percent growth. Same goes for JP Morgan analyst Ehud Gelblum, who is slashing his forecast from 8.1% to 6.1% for the next year. Both analysts blame the U.S. economy, but say that growth in Europe is already slowing and that growth in China will continue, but at a much slower pace.

Of course, market saturation won’t help the stocks of cell phone makers. The U.S and European markets are just about full-up on cell phones, which have become as ubiquitous in households as toasters or televisions. But with the struggling economy, cell phone consumers are hunkering down, often switching to flat-rate, lower cost models that allow them to keep a lid on monthly phone bills. It’s a prickly issue for Apple and Research in Motion, makers of the iPhone and the Blackberry, in particular.

One rule of thumb is that consumers, especially white collar workers, are so addicted to their Blackberries that they won’t trade down no matter what.

That’s all fine and good, but the trouble begins when new users shy away from pricier iPhones and Blackberries and opt for less expensive cell phones and cell phone plans. The cell phone industry ha a “churn” or “turnover” rate that benchmarks how often cell phone users change models. In past years, the trend was to trade up to pricier models. Now, according to the market research firm Churn, cell phone turnover rates are tending downward, at 0.4% for the third quarter of 2008. Says Churn, “Those figures could indicate that Americans are looking to low-cost, flat-rate cell phone plans as a way to trim expenses.”

Interestingly, a silver lining of sorts exists in technology’s shiny toy sector. Sales of big screen televisions are expected to remain stable, and the same goes for video game hardware, according to the Consumer Electronics Association. Unless prices come way down, I find that hard to believe, given dour consumer sentiment right now. Maybe people feel that staying home is akin to saving money, so they’re outfitting their abodes with nice TV’s and video games to entertain the family in tough economic times.

If so, they’re not feeling the same love for their cell phones. And that could spell trouble for the Apple’s and RIM’s of the world over the next few months.