As a person whose dislike for the New York Yankees (aka the Evil Empire) is on a par with what those Canadian demonstrators apparently think about the U.S. and/or President Bush, I must admit to getting a bit of schadenfreude over the Giambi/steroids affair, subject only to concern that it would end up helping the Yankees by allowing them to wiggle out of what has become an inconvenient contract. (For them, even $80 million probably can't be described as worse than "inconvenient").
But of course there are broader implications here, not to mention that I am disposed to admire Barry Bonds although the leak about his testimony is no more surprising than that about Giambi's.
A point about the steroid controversy that not everyone gets is that the issue here is really, in a sense, more about the players than the fans. The reason for banning steroids is to protect the players. You may want to do this for paternalistic reasons if you think lots of players who would be inclined to take steroids are making a serious mistake in terms of their own long-term interests. (Bonds and Giambi have certainly been well-compensated for any enhancement to their stats, but lots of others may not be, perhaps even at the college level or lower.) Or, less controversially if you don't like paternalism, there is a collective action problem here. Players are engaged in an arm's race, and all are worse off if they must do more just to stay in place. (Without the illegality, this is the story behind Jim Courier's rise and fall as the men's #1 tennis player - he raised the bar in terms of physical conditioning, and trounced the field until everyone else realized they had to join him.)
From a fan standpoint, steroids hurt the game only in the circular sense that, if people care about them then they care about them. I personally find Bonds' achievements amazing no matter what. And of course there may be systematic changes to the balance of forces in the game, e.g., more home runs, which might be good or bad for fans without regard to whether they come for steroids. It certainly isn't unreasonable for fans to hate steroid users because they are cheating in a manner that endangers their fellow players. But player welfare is the issue here.
Separate question: will we soon start hearing about amazing late-career power pitchers and steroids? After all, you need flexibility, not just strength, to hit like Bonds or Giambi, and maybe that implies power pitchers can benefit too.