I upgraded a Dell Inspiron N5110, fairly current specs, at the release and was impressed at first. After way too many phone calls to tech support and hours of wait time and actual time fixing problems, I do not recommend upgrading. Every problem I have had was due to known issues that had not been addressed before the release. Give MSFT some time to fix the many, many bugs before switching.
When it works, it's great, it just does not work as well as 7. Lack of support for BluRay is still a big issue for me.