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Looking at the DG413 data sheet, it appears that this particular switch uses a low level logic signal, 2 volt max for switching which will need to be taken into account.

Actually, it's a 5 volt switch... that's how digital logic works, for this board anything under the 0.8 volts is "Low", anything over 2.4 volts is "High".  For my own design (I've got 7 stomps in one box) I'm going to use an Arduino to sense the momentary switches and toggle the appropriate digital switches.  With this setup, one Arduino can control all 7, and I can even make "setups" (i.e. when this distortion is engaged, turn the other 3 off, or pushing this button engages this configuration, etc).   It's something I've wanted to do for a while anyways, and getting completely pissed off at those godforsaken blue 3pdt switches has gotten me off my keaster to do something about it.   
Parts and PCBs are ordered...  I'll know how it all works in a week or two. 

Yes, I looked at it earlier... unfortunately, I didn't have that particular part number handy when I was talking to Don (the engineer).  I'll show it to him tomorrow, if he happens to come by the plant, but I went ahead and pulled the trigger on the DG413, since I found them at FutureElectronics for about 1.25...   Since I'd need 3 of the H11F1 to build one switch... not to mention more hardware, I'm personally going to run with the DG413.

I just spent some time talking with an engineer who specializes in hi-fi audio devices (He mainly designs speaker/amplifier systems).  I was asking him to recommend a good optocoupler for the task, and he replied "none of them".  He said my NLS32 switch probably did sound fine to me, but when you have 4 or 5 pedals in the chain, that high resistance will suck the tone out, and I'll need boosters galore to make up for it, i.e distortion... most of the optocouplers out there aren't designed for audio, and introduce... distortion...   He pointed me to a DG413 digital switch http://www.mouser.com/ProductDetail/Intersil/DG413DJZ/?qs=%2fha2pyFadujfDDcW%252bvCOvHF8bn6BtXIPejAzdL9RvAk%3d... 4 switches in a PDip16 package, 2 switches NO, two switches NC..  And they're pretty reasonable (about $2.50 at mouser, or $2.02 if you buy a tube, compared to $9.00 for 3 NSL32).   Since the chip has two NO and two NC, one could design a circuit with a SPST latching switch and still include a status LED or run an SPST momentary into a bistable flip flop (and yes, still have the LED). 
Of course, the engineer won't draft the schematic for me, but he assured me that if I could design the NSL32 soft switch setup, this would be a cakewalk. 
So off to order chips and load up DipTrace.

The ones I've ordered from Tayda are the generic blue ones... Of the 7, I've used so far, one shattered internally after about 20 clicks, and 4 of them send pops down the audio chain (but they didn't for the first 100 clicks or so)...  The other 3 are holding up (for now)... but any popping is unacceptable when you're playing in a worship band, playing a nice slow song, about to switch to that killer slow lead and BOOM (Boom boom bm bm, thanks to the echo). 
I just spent the last day breadboarding an opto based solution with 3 NSL32s I have in my stock and an arduino to switch them...  At least on the breadboard, it works like a charm, tomorrow it's putting them into a PCB...   
Any suggestions on the best optos to use for this without breaking the bank?

I've usually replaced 1n34a with 1n270 with good effect... but... you should know that Tayda has the 1n34a right now for $.24... They're almost always out of stock on these. 

I finally got my Afterlife up and running (I put it on the "WTF did I do wrong?" shelf for a month as it didn't seem to work at all, and noticed the other day that I had the Vactrol reversed... considering that I build circuit boards for a living, that was a pretty boneheaded move).
So, sounds great, but I'd love to get a little more control over the Attack and Release. 

It looks like I could put a 50k or 100k pot in series with R7 to make an adjustable sensitivity.. this should translate to an adjustable attack, but I'm at a loss as to how to make a pot setup work with C3 for the release... I don't think an RC filter is going to do the trick...