RIM’s Blackberry smartphones are no longer the default choice for corporate employees, a pair of stories released today seem to imply. Computer manufacturer Dell is planning to move its 25,000 employees from RIM smartphones to its own Dell Venue Pro – a phone running the new Windows Phone 7 operating system. Later, the company will permit Android phones as an alternative.

And Dell isn’t the only RIM-switcher making headlines today, either. Two of the biggest U.S. banks, Bank of America and Citigroup, are seriously considering the iPhone, it’s being reported.

While Dell’s news may be more about its own self-interest – after all, it’s switching from RIM to a product it intends to sell – the banking corporations decision to mull the iPhone is an example of an ongoing trend.

Last month, Apple reported that 80% of Fortune 500 companies are testing the iPhone, including Procter & Gamble, General Electric and JPMorgan Chase & Co., the latter of which is also considering Android, says Bloombeg

The article also cited an August survey by Sanford C. Bernstein & Co., which found that 74% of U.S. and U.K. companies now let employees use non-Blackberry devices and in the U.S. alone, that number is 83%. Cost and employee preference were the two main reasons for the switch, the poll found.

Cost savings come into play when a company can either partially or entirely eliminate the need for Blackberry servers. In Dell’s case, for example, Dell CFO Brian Gladden told the Wall St. Journal that the company will save around 25% in mobile communication costs by moving off of Blackberry.

But for the employees whose Blackberry phones would have to be ripped from their cold, dead hands (as the expression goes), it’s not all bad news. According to Bloomberg, Bank of America’s 284,000 employees and Citigroup’s 258,000 employees would simply have more choice in devices if the companies decide to permit iPhone usage, it wouldn’t be a forced switch.

sarah perez