I too have had no problems with SP2 and as its been about a while now most software problems have been solved with patches available from the software websites. But I haven't needed any patches everything has gone fine for me. I hope I'm not tempting fate by saying that.
We have heard a helluva lot from the minority of folk who installed SP2, and very little from the majority who had no problems. I do believe there`s a part of the Windows Upgrade site that asks you to read this befor installing SP2. Apologies if this is not right. Have a look and then act in your own interests. You can always uninstall as matty_92 said