Even though Microsoft says it will no longer sell Windows 98 and it refuses to offer support for Windows 95 and 98, a survey of 670 companies reveal the operating systems are still widely used. Some businesses report it is too costly to upgrade.
Assetmatrix did a survey and found that 80% use 95 and 98 on some office computers. 14.7% of the computers used 95. 12.5% had Windows 98. More than half had Windows 2000. Windows XP was only found on 6.6% of the computers.
Microsoft will not allow security patches for the older operating systems. A business owner says "it means...the Internet viruses, worms, Trojans and who knows what else will have 'free reign' of the older machines compromising the entire Net." Source