I upgraded from Quicken 2007 Premier to Quicken 2010 Premier. I waited to upgrade because of negative reviews in previous years. I should have waited again. I neglected to upgrade my account summery page. I should have. The upgrade went without any obvious problems, but after processing my old data file, I saw that my net worth was significantly higher than it should have been.
One of my 401k accounts was a -$50,000.00. Somehow, in the upgrade process, a transfer got counted twice. Many of my mutual funds have the wrong share count or price. I believe they will be OK after they are updated with December 31, 2009 data, but the histories will still be bad.
I thought the 2007 home page was much nicer than the 2010 home page. I saw some new bells and whistles, but I did not see anything that made me say, "boy am I glad I bought Quicken 2010".