Course, I don't quite understand your comment? The ONLY thing Soundtrack/FCP has over Vegas/Acid is the ability to lock them together perfectly, and read markers from one to the other. While that's significant, in the whole scheme of things, it's minor.

I'm working with the FCP Suite now, and while Soundtrack Pro is sweet, it's not hing really new or that impressive. ACID Pro has as many strengths.

Sony just really needs the marketing muscle. Hardware support would be cool too, but we're much of the way there.

I quite liked the following feature:

Action-based waveform editor

Also the following less important one:

Ambient noise print
Get rid of unwanted noise and save time when preparing dialog tracks or editing live recordings. Set an ambient noise print and Soundtrack Pro automatically fills deleted audio segments with natural-sounding room tone or environmental noise.

I always did this manually, and it's certainly not a huge deal, but it would have saved me some time in a recent nasty audio project.

Do these features have an equivalent in Vegas and/or SF?

They would be good time savers for me.

The action list, I didn't find valuable, but I can see how some folks might.
Regarding the noise print...there is a custom method of doing this. I'll ask the dude that wrote it if it's shareable. (Vegas script)
In FCP/Soundtrack, this doesn't do a great job, because the ambience loops sound odd (to me, anyway)

If you can shake loose the Vegas script for "noise print replacement" I'd be grateful.

So you can't use any ambience loop (including your own) in Soundtrack?

The ambience loop is room tone, not a loop like you'd think of in ACID. But if you wanted to use a loop like ACID, of course you can. Soundtrack matured a lot in the last 9 months, it was an ACID wanna-be, now it's got teeth of it's own. As it should. The former ACID product manager is the Soundtrack product manager. He learned from the best!