Hi JBeece,
I've been researching the best way to do the same kind of thing recently.
I don't have experience with X10 cameras or the iWatchOut software that integrates them into the ActiveHomePro suite. I think it will do at least some of what you're wanting, especially if you add in 3rd party programs like X10Dispatcher and the AlertDialer for X10. I recommend looking into it, and I hope that others here can tell us more about it, but at the same time, do compare it to BlueIris software ($39 for the full version), which works with up to 16 webcams. It will do everything that you said that you wanted and more. When motion is detected via a webcam, networked IP camera or other video input (and you have lots of flexibility about what constitutes motion - lighting and color change levels, how many changes, image de-noising, selecting which part of the webcam view to detect motion in), it will run a webserver and dynamic webpage with streaming video and viewable clips and snapshots (integrating sound from a microphone if you want), e-mail you snapshots and alerts, phone you using a computer modem, MSN-message you, upload clips to your FTP site, run external Windows commands, send you screen shots if an intruder starts trying to mess around with your computer, and I forget what else. It has a number of its own security features, and can be set to run invisibly and/or automatically whenever Windows loads up, before you even log into it. You can get it to automatically add time-date stamps and watermarks to each clip and snapshot, which I highly recommend, so it should be possible to use the clips as evidence in court. I'm still trying to wrap my mind around it and all its configuration options. I think I need a day just to learn it all. You can try it out for free for 15 days; it's at
www.blueirissoftware.com. One thing I'm pretty sure that BlueIris probably has over X10 solutions is that you have a wider range of webcams to choose from, and you can often pick up a webcam at a local store on a sale for $10. I recently got two Creative Webcam Live! webcams this way. Probably the X10 camera with iWatchOut and MyHouseOnline solution has the advantage of giving you more home automation options over the internet.
I'm hoping to be able to integrate my BlueIris setup with ActiveHomePro/OnAlert and my X10 security stuff, also just recently bought. X10 motion detectors, door/windows, and lamp modules provide the "Lights," BlueIris the "camera," and X10 ProtectorPlus and mini-powerhorn the "action." Both ActiveHomePro with SDK components or (X10Dispatcher) and BlueIris can be made to run external Windows commands, so that should be one way of getting them to send commands to each other. I'm not sure that I'll need to go that far, though, because when X10 turns on and flashes the lights, that will normally constitute motion in the webcam picture and activate the BlueIris activites. Or when X10 sounds the siren(s), BlueIris can be configured to detect the loud noise with your computer microphone, which is another way to trigger its features. I would like to be able to have my X10 keyfob remotes be able to arm and disarm not only the X10 security setup, but also BlueIris; probably that's where being able to run external Windows commands will come in handy.
About where you're aiming your security cameras, does your apartment have a balcony/patio door? If so, you might want to get another camera aimed at it. Good luck there.