If you're talking about healing / mana pot injectors on Live, you can top-off an injector with another one. For example, I finished last night's raid with 14 charges on my healing potion injector and had one with 8 charges in the bank. Drag the bank injector and drop it on the bag injector, and presto! 20 in my bags, 2 in the bank. I think that change happened with 2.4?

They aren't charges. They are a splittable/stackable item. I can take any newly created mana/health pot injector and split it back into 4 stacks of 5 if I really wanted to.

Seeing as the new content patch will be out soon which will include Inscription, does anyone know the herbs and materials required to get inscription to 375 to start farming a little early?

I'm already doing that, and while I'm not sure of what specifically, I'm basing what I gather off of requirements to level Alchemy (only so far as herbs go.) I figure if I overshoot, I can sell or trade off the rest, and if I undershoot, it won't take me very long to go gather up some more. The real question will be the non-herb materials, which I have yet to do research on.

I'm not sure when this was put into effect, but long before 2.4. At least as far back as 2.3, perhaps farther. Most people are just unaware of it because the thing is named so oddly.

One thing that I was wondering - given the Blue post about the pre-WotLK patch -

Browsing through pre-expansion items on the various WoW-data sites implies that the items will be modified to fit the new `spellpower` mechanic. Specifically, items that are currently geared towards healers. Including crafted items.

This is particularly noticeable in the cloth armour area, which has far more dps-related characters than healing-related (including priests in both categories).

Normally, there would be a narrow window post-expansion where this would be noticeable, but it seems likely that the spellpower change (as a major part of the new mechanics) will be a part of the pre-expansion patch. Speculation, yes, but likely. If true, this gives a significantly larger window of time where items previously of interest only to healers are dps-competitive. Additionally, the healing items are substantially cheaper to craft given average realm prices.

Oddly, the exception I have noticed is in the bracer enchant - where the healing enchant appears to be unchanged while the dps enchant has been modified. I can only assume this is to prevent early obsoletion of the bracer-spellpower enchant, which is already only slightly more powerful (15 spell damage rather than 10) for a much larger cost.

It depends how the trinkets hold up (and any BoP smithing gear), and whether there's progression with them too.

The thing about BS & JC is that you can chose which extra stats you get. With LW/Tailoring/etc you are funneled into a select few (AP, spell damage, etc). A minor inconvienence for DPS classes, but for a tank, the ability to select a very specific stat is much more important.

I'm wondering about the ease/difficulty of racing to 450 profession skill for the server-first achievements. Is it possible at this point to reach 450 at level 70 in any profession in a few hours, assuming a limitless supply of gold and an abundance of starting-zone level mats up on AH?

That last assumption, upon further thought, seems unrealistic. Not many will bother posting their gathered mats up on the AH right away, and certainly demand will be greater than supply. I would think it would take the cooperation of a few friends or your entire guild immediately sending you what mats they gather in the opening hours at the very least.

While it's definitely a net loss in total stat points, the lack of them being unique-equipped does mean you can just use three of your optimal stat. I wouldn't underestimate getting an extra 21/33 of your optimal stat over people without Jewelcrafting.

Edit: And as Phlis points out below, not having to compromise statwise for meta gems is a pretty big benefit. You'll also be able to pick up a few more socket bonuses without sacrificing stats which is also a not to be underestimated benefit.