http://news.bbc.co.uk/2/hi/technology/3557952.stm
At the time of writing it had reports from 152 users about their experiences.
Although 43% said the SP2 installation had gone without a hitch, 49% of those contributing had problems ranging from minor to severe.
A few contributors said they had to completely rebuild a system before they could get the update to work.
Many others, 30% of those responding, said they had minor problems such as clashes with non-Microsoft browsers or applications.
Some had to tweak hardware settings to get machines running as they did before SP2 was installed.