Look guys, I've played with 2 900s. There is not, I repeat not, a lag issue. When you say "lag" you automatically make people thing of actual lag, like Android has. Let me explain what is going on here:
Firstly, I almost promise you that all these people making this claim are Samsung handset owners. This "lag" isn't lag, it's scroll speed. That's it. No lag whatsoever. The reason I say every claimer is a Samsung handset owner is because Samsung handsets have a very fast scroll speed. I've used HTC handsets and the scroll speed on them is the exact same as on the 900. What I'm saying is, if you have only used HTC handsets, you won't be able to tell any difference between yours and the 900, because neither your phone nor the 900 has a scrolling issue. I just wanted to clear that up. Do not worry if you're planning on getting the 900. There are no issues whatsoever.