People say that almost every year. It is basically code for, there is not a no brainer #1 pick. And it's true, there is no Shaq, Duncan, or Lebron in this years draft.
Just looking at recent history, people said the same thing in 2006. And the #1 pick was a bust in Bargnani. However, the same draft has already given us Lamarcus Aldridge, Brandon Roy, and Rudy Gay as the potential stars along with a host of good role players.
In 2007, the draft was supposed to be terrible after the top 2; however, Horford, Hawes, Wright, Thadeus Young, Stuckey, Wilson Chandler and Rudy Fernandez, etc have already emerged as legitimate prospects.
2005 was also supposed to be mediocre. Heck the #1 pick that year was Andrew Bogut. However, after that we got Deron Williams, Chris Paul, Raymond Felton, Danny Granger, Nate Rob, Cisco, David Lee, etc. That draft also had Bynum and Louie Williams, but I didn't include them because they were high schoolers and players like them will not be eligible in this year's draft.
In fact the only truly terrible draft in the last 20 years was 2000, where the best player was a second round pick (Michael Redd) and the second best player was either Hedo, Kenyon Martin or Mo Pete and there were a ton of players who were out of the league in less than 5 years.
Point being, it is way too early to write off this draft. There is a lot of potential talent out there and certain players will elevate their status greatly during the college and various FIBA seasons. The only thing we can definitively say is that there is no slam dunk, franchise player for whatever team gets the #1 pick. There might be some actual talent evaluation required for all the lottery teams.