i bought mine around 2 years ago and extremely regretted not buying an n97 at first cause all the bugs in pr1.0 and me and that not having much prior experience with linux thought the phone was a joke but now i wouldnt switch it for any other phones (the other day my cousin came to show off his iph4s and slander my "fossil" but man should you have seen me when i wiped the floor with spending the entire next hour showing him 10000000000 things possible only with the n900)
On the verge of getting a second one. So, I guess the answer is "no". The only regret I have is that I did not take my own thoughts seriously: The thought that this n900 would be a one time deal and that I should've bought two to begin with.
Many people who regret buying N900 are long gone. The only ones left are diehards. Hence you should not be surprised to get highly skewed opinions.
I no longer use mine but I don't regret having bought it. Got lots of good use out of it. But the N900 is now two years old and a lot has happened in mobile devices during that time. I had planned to get an N9 but Nokia seems to have made a complete botch of that in the US.