No, what you hear on your 06 LE is a factory screw up where they used main bearings that are not the correct size! I have 2 06 LE's with the same sound, and it is not the same sound as my brother in law's 02 Hayabusa. I have one in the shop that is being repaired as we speak and I had to bitch like we were all going to die tomorrow to get it done. The mechanic didn't know what was wrong but agreed that the noise is not normal, then yesterday he spilled the beans that there was a huge run of 06 LE's with incorrectly sized main bearings. Suzuki is not big on warranty repairs for this because according to them there have been no engine failures reported. If the rev's are below 3,200 rpm though I sound like a diesel truck coming down the road.
If you have the chance to compare your 06 LE with another Busa andn notice the sound is not the same you better call Suzuki USA now.