My questions are:
1. Does it allow merging m2ts files into one big file without transcoding?
2. Is it optimized for multithreading on intel's core i7....? in Tomshardware processor charts premiere cs4 does and it actually takes half the editing time when using core i7 than quad core.... does that apply to vegas?
3. Does it allow outputting AVCHD files with maximum bitrate of 24 mps for those of us like me having a new canon AVCHD camera?

Simple answers:

1. No

2. Not sure about Core i7 but it loads all 4 cores evenly up to 95% on my Q9550 when rendering AVCHD

3. No, 16Mbs maximum