Should anyone pay attention to Newsweek Polls?

Has anyone else noticed the huge, massive swings in the Newsweek poll results. In the newest Newsweek poll (7/09 to 7/10), Obama is up by three points. In a poll a few weeks ago, Newsweek got all sorts of publicity for having Obama up by 15 points. I just noticed this huge swing in looking at RealClearPolitics. Newsweek asks if Obama's "Glow Fading?" and states "What a difference a few weeks can make." Well, it turns out the new poll assumes that 32 percent of Americans are Republicans, 32 percent are Dems, and 36 percent are Independents. The previous survey assumed that 26 percent of Americans are Republicans, 38 percent are Dems, and 36 percent are Independents. Do you think that difference in weighting might explain the change? Do you think giving more weight to Republican preferences and less to Democrats would raise McCain's showing and lower Obama's? I seem to remember that Newsweek's polls were all over the place during 2004. Possibly this type of polling gets more attention and gets people to talk, but it is also pretty sad that Newsweek can't explain the changes with the cause that they obviously know explains the result.