Since the M doesn't come with a stand or wall mount, what are you guys using for a mounting solution? I figured the 600M is so svelte that it deserves to be mounted on a wall (like a piece of art). Then of course, there's the issue of my 3 rowdy girls knocking over the TV if it's not wall mounted

I just ordered the Omnimount ULPT-XA low profile tilt mount. You can get it for 1/2 MSRP on Amazon. I don't know if I'll use the tilt feature, but it's low profile (1.5"), so it seems like the best of both worlds. One of the Sound and Vision magazine editors used this mount for his Pio Elite.
Here's a list of compatible wall mounts. I took some of them from the
Signature 141 owners thread. I assume any mount that works with a 141 will work with the 600M. This is NOT a complete list. There are cheaper mounts from Monoprice that may work, but I didn't investigate them.
Sanus VMPL3: Comes with low profile (1.5") AND tilting attachment (2.5). You use one or the other.
Peerless PLA60: Articulating wall arm, you need the adaptor plate too (PLP-NEC61)
Peerless SA760P
Peerless ST670
Peerless SF670
Pioneer KRP-WM01
Omni Mount U3 Tillt
OmniMount ULPTX (low profile)
OmiMount Architectural cantilever
Promounts UF-PRO400
Chief LSAU, LSMU (flat), LTAU, LTMU (tilt)