Not a whole lot of major releases I've noticed for the month but a few potentially interesting items.  Anything I've missed?

New albums
08/09: Lord of Vermilion Re:2 Fan Kit   [Play-Asia]  (Final Fantasy, SaGa, Mana & Valkyrie Profile arrangements by Sakimoto & ex-Square artists)
08/13: Nanosweep 12
08/24: Devil Survivor 2 OST (Kenji Ito)  [Play-Asia]
08/24: Monster Hunter Ethnic Sounds ~Ethnic Instrument Arrange Album~
08/31: Taito Retro Game Music Collection 2 Action Cluster

Reprints/Compilations
08/24: Sonic Heroes OST 20th Anniversary Edition  [forum topic]  [Play-Asia]

Pack-ins
08/30: Otomedius Soundtrack  (U.S. release)

Normally I could not care less about Lord of Vermilion (didn't like the first two OSTs at all) but seeing that Lord of Vermilion Re:2 Fan Kit has FFIV, FFVI, FFIX, Secret of Mana and more arranged by the likes of Sakimoto, Yamazaki, Sekito, Kawamori and others has me interested.

If the productions values and arrangements are of high quality Monster Hunter Ethnic Sounds ~Ethnic Instrument Arrange Album~ could give the Genso Suikoden albums a run for their money.

Curious about the Sonic Heroes OST single-disc edition.

Oh and Taito Retro Game Music Collection 2 includes Rastan!  I have no idea what the music sounds like but that's one of the more nostalgic arcade titles of my childhood (even though I never was any good at it).

I think these ones also deserve some attention:
N/A | Deus Ex: Human Revolution Soundtrack
AUG-8701 | Aiyoku no Eustia Original Sound Track
KSLA-0073~5 | Rewrite Original SoundTrack
N/A | Akaya Akashiya Ayakashino Music Collection

The new Deus Ex is scored by Michael McCann and I hope it follows the spirit of the first game (which was awesome by the way). Then there is a huge release for the visual novel Aiyoku no Eustia, which I think is kind of exceptional for VNs.
Next is the new work by Key Sounds for the visual novel Rewrite. We already got a small arrange album (Soil) for that game in June, which was really great IMO.
Last but not least there is a new (full) soundtrack work by Akiko Shikata. I think we can expect something on the level of Hanakisou. Very excited about this one, easily my personal favorite for this month.

08/24: Minna no Rhythm Tengoku Complete Music Collection

As mentioned in the 8/2011 Release Purchases thread, the release pamphlet reveals an album spanning 177 tracks spread across four discs.  Not only are we getting every core song (including accompanying tutorial and intro BGMs), but also Perfect Versions for every stage level, and full-length versions of the five vocal tracks.  My only hope is that they don't botch the sound mastering like they did on the Rhythm Tengoku Gold OST.

There's a terrific game rip for Minna available, and I reckon I'll still be listening to it every day up till the soundtrack's release date.  Some of my personal favorite songs so far:

2nd Remix,  Monkey Clock,  See Saw
Bird Flock,  Book Girls,  Matsuru Doll
Recess Date,  5th Remix,  Staff Credits ~Our Generation!

My first "purchase" in August is going to be rather inexpensive: Harmony of a Hunter. It also my most anticipated album of the month.

I'm somewhat dubious about LORD of VERMILION Re:2 FAN KIT because the Basiscape crew from LoV 2 are not the arrangers. The large amount of FF music is naturally magnetic, and that is a field I can not escape.

My highest priority purchase is OverDriver.

I did not know that the Lord of Vermillion release would have those tracks on there... I must get a copy myself now... *adds to growing CDJapan order*

Ooooh, that sounds interesting!
I didn't give a hoot about the first two soundtracks either, but I'm always up for some remixed classics!

Damn, I got all excited and then found out Sakimoto is just arranging four tracks.. three being original compositions and one being the Uematsu-composed opening theme.  Would have loved to hear more FF arrangements from him.  The ones he did in FFXII left me wanting more!  Mitsuto Suzuki's take on the chocobo and moogle themes should be interesting though.

My OST came in earlier this week, and I've been able to give this bad boy a thorough listen.  I can happily report that the mastering is in no way botched, and sounds downright amazing overall. 

My only complaint is that the "Perfect Version" tracks are slightly less crisp and clear sounding than their original "music only, no sound effects" counterparts.  I suspect this might have been done to better match the volume levels of the in-game sound effects, but as such, the Perfect Versions give off more of the feel of a (really good) in-game recorded presentation rather than a CD mastered one.