I'm thinking about getting one to control my keyswitches so I can do them with my feet.

I can see it can send note on/off and controllers, but I'm unsure how they are sent since it's a pedal board.

Do the pedals send note on/off at the same time when you press one of the pedals, or can they be held down for the note on and then when you release they send the note off like a keyboard would?

The latter.   Any pre-programmed MIDI Note On Number from 0-127 on a switch press; held until release of the switch sending the complementary Note On / Velocity of 0 (alternate "Note Off").  Of course, monophonic (one note per-switch), but 10 note number values per-bank.
 
Pressing another switch simultaneously will stop the original note from sounding, and replace it with the last note pressed.  The unusual quirk here is that every Note On velocity value is 64, with no adjustment possible, in the fine tradition of non-velocity keyboards from the dawn of MIDI.

Hmm, monophonic, hadn't thought of that. That's a problem because a lot of my important libraries uses one keyswitch for selecting articulations and another for effects or pitch or changing rhythm.

Maybe something like the Keith Mcmillen 12 Step MIDI Foot Controller would be better, it looks a little plasticky and not as robust as the Behringer, they have it at my music store so I'm going to give that a try.

Thanks.

Not being polyphonic shouldn't be an issue if you're using it for keyswitching.

Several of my libraries (From 8DIO) have 2 or even 3 keyswitch areas, one for articulations, one for pitch (Patterns) and 3rd for effect (reverb, echo, other effects) first one at lowest octaves, second and 3rd at high (c5+) octaves.

I got home today with the Mcmillen 12 Step MIDI Foot Controller, guess what...

  No software for windows, wonderful so you can't edit note values or CCs on it.  It's also not made for people with clown feet like mine.

Said bah (Well the more rude version of bah as it were hehe) returned it and got myself a Roland PK-6 ( http://www.roland.com/products/en/PK-6/ )

I'll have to live with looking like the greybearded  dude in the corner with the organ at old people parties

It looks like I waited a little too long to add to this.  In my defense, I usually get virtual rolling eyes when I mention an event processor.  It may be the sysex programming (although the Programming Tools app creates it for you), or the the extra piece of hardware + expense.
 
I use the Event Processor Plus to translate the 5 Program Changes, switch CC's, exp. pedals' CC's, and MIDI Note on an FCB-1010 to something that I can use (usually MIDI CC's distributed throughout my pedalboard).  It's small, it's powered by the MIDI signal, and it retains its current programming on power-down.  Once you've programmed up to the 10 (or 32) event maximum, there's no need for a computer again until you need to re-program the device.
 
Nothing against the McMillen products; I've considered those versatile devices many times myself.  I just wanted to point out an alternative.  An FCB-1010 and an event processor cost close to one of the McMillen MIDI pedalboards without the almost-mandatory MIDI-DIN interface.

I got the Roland PK-6 instead, much much MUCH better hardware and just standard MIDI, although 4 times as much as the FCB1010

I use BOME MIDI translator, there's no MIDI or SysEx you can't catch and reconfigure on the fly, I use it a lot to create MIDI to keyboard mappings or wrangle MIDI devices into working the way _I_ want.

you might want to have a look at this

Thanks Jonesey, but I've already got the Roland PK-6.

As I had the 12 step unit home I can say a few things about it...

Very plasticy and the pads you need to step on is WAY to small to be useful.

The store had the softstep to, same thing way to small to be useful for precise control.

You can't feel the pads since they are so small, if you're using shoes you have almost no control.

  All the pads send out controller data when you press up or down, but again because they are so small, it's basically random. For example playing a piece where on a note you need exactly pitch wheel half up to get a good grace note... forget about it, not going to happen. I guess if you assign it to filter cutoff it could work, but any kind of precise pitch or mod wheel emulation is not going to work, it's like trying to use mod/pitch wheel with mittens on.