I'd like to thank readers Jay Revell and Paul Nagel for helping me ferret out the truth about what IE 5.5 SP1 really consists of. None of that is true. IE 5.5 SP1 consists of 14 bug fixes, and does not add any functionality to Internet Explorer. So don't go looking for new features. The more interesting story is how IE 5.5 SP1 has performed for people who've tried it.
Some people report very positive results, while others report very negative ones.
There's no reason to rush into this update. Windows Me users are the least likely to have problems, although they're not immune. If you currently have IE 5.5 installed, and it's running well, hold off. If you're running IE 5.01 Service Pack 1, leave well enough alone. No promises though.