BOSTON – As the latest Microsoft-focused virus wreaks e-mail havoc around the Internet, credit union IT managers wondering if they should branch out a bit may find they're not alone. A new Yankee Group survey of organizations the size of most credit unions reveals that many small and medium-sized businesses (SMBs) are deeply concerned about depending too heavily on Microsoft. Approximately 43% of respondents (with two to 499 employees) to the research and advisory firm's SMB Infrastructure Survey said they were concerned about becoming overly reliant on the software giant's products and services. And 72% of those said they are actively seeking to diversify. According to senior analyst Helen Chan, "The SMB market is the next big thing for Microsoft, estimated to be a $10 billion business for the company by 2010. However, Microsoft is not alone in its SMB ambitions as vendors such as SAP, Oracle, Siebel and IBM are aggressively moving down-market. "There's no question that Microsoft commands a strong presence in the SMB market, but this fear of Microsoft over-dependency will certainly open up opportunities for competitive vendors eager to sneak in," she said.