From a personal standpoint this decade's been pretty good. I've been blessed with a wonderful wife, two beautiful daughters, a home and a good career. While there's been a few scary times, my mom's breast cancer, an autoimmune disorder that my daughter developed several years ago and my sister being in a very bad car accident, we're all still here and (now) healthy.
The technological breakthroughs have been nothing short of incredible. One has a world of information literally at their fingertips, at any time, through smart phones and/or home computers. Bluray, HDTV, WiFi, broadband internet, etc... Medical breakthroughs have also been amazing.
I will also say the cars of this decade have been amazing. The recent Corvette ZR1, the Lambo Gallardo, the Nissan GTR are all incredible machines. Most I-4s today are making the same, if not more, horsepower than V-8s 15 years ago. The construction of even the cheapest vehicle on the road is probably 10x safer than the most expensive vehicle just 10 years ago. And most of the vehicles look better to, though crap like the Nissan Cube might make me think twice about that statement.
All that being said there's nothing culturally that really set this decade apart from the 90's. Television today is nearly unwatchable. There's no great dramas like ER. There's no great scifi like TNG or Babylon5. There's no great sitcoms like Seinfeld or Friends. There's nothing new in regard to music. There's been no new edgy (or just plain likeable) music such as that from Nirvana, or AIC or Tupac or Garth Brooks (to pick from various genres). In regard to movies, if you don't make it to the theater within a couple of weeks of the films release, it's gone. Not that it's a bad thing. The video's out within 4-6 months of it's theatrical release anyways and most of the movies out there are not very memorable. There's the occasional "diamond in the rough" such as the LOTR movies.
The fashion too has been somewhat dull. The 80s had funky hairstyles and even funky-er clothes. The 90s had it's own unique look as well; The hairstyles ranged from MC Hammer's zig-zags, or Vanilla Ice's hair to long floppy hair to the "ceasar cut". As far as clothing there was flannel (grunge) or super baggy jeans or overalls. There was Doc Martins, there was FUBU, there were Starter jackets. I won't even get into women's fashion.
This decade... well there's some differences than the 80's and 90's but there's many similarities and its all dull IMHO.
The previous decades seemed so much better overall than did this one. I always wondered if it was just me, but judging by this thread apparently not. Like I stated, from a personal standpoint I have a great deal to be thankful for, but looking at the "bigger picture", this decade blew chunks.