I think Katy is a lock for #1 this week. I could see CG getting the most weeks at #1 by any song in 2010 as it is showing no signs of slowing down.
MY PREDICTION
1. California Gurls
2. Love the Way You Lie
3. Airplanes
4. OMG
5. Billionaire
6. Cooler Than Me
7. Ridin' Solo
8. Dynamite
9. Your Love Is My Drug
10. Alejandro
it'll probably last 3 more weeks, sales have to die at some point.
"Party In The USA", "I Gotta Feeling", "Tik Tok", and many other big songs have lasted months in the Top 10 of iTunes selling. "California Gurls" won't be doing 300k+ every week of course, but it won't just die. On top of that, it's not peaking at radio yet (besides maybe Pop soon), but it will not quickly fall off either. Similar to how "TiK ToK" fell slowly once it peaked. 3 weeks is a rubbish prediction..