Good point. If you're going to have more than 8 LAN nodes connect to one gateway node, then you'd better have the gateway node set up so it can receive incoming connections. Otherwise, while the gateway node has 8 or more connections, it will not try to add any more outbound connections. As the outside nodes you're connected to come and go, it doesn't make new outbound connections to replace them. You'll be fine if you can accept incoming connections, then there will be plenty of others connecting to you.
The Windows Client had it's own static IP with port 8333 open for it, I could see from the gateway device that it was connecting out to other peers and other peers were connecting back in. But after the 8, it's like it quit connecting out to peers and after a while the incoming peers stopped as well since it appeared to only be concerned with the peers on the LAN vs the WAN. The behavior of the Linux client is different though I've noticed, even if 50 people are connected to it, it will still seek outbound connections to other peers and inbound peers continue to trickle in as well.
While this will only be a problem for people like me that have hundreds of PCs at their disposal, the reverse is, one could setup PC(s) to connect to a single client 8 or more times and then after a while, the poor windows client would suck itself into it's own matrix world where it thinks it's on the network solving blocks, but it's really trapped back in time.
This is just a theoretical attack of course, I'm not going to lose any sleep over it, but I figured I would throw it out there for the future. The easiest way to negate this would be to put in some self-checking code for IPs. Basically, have to check that is has 8 connections or more that are NOT from the LAN/Same IP Address/etc when it's running as a dual node/client mode.
, confirmed NOT to be a bug when testing Windows 2000, XP, Vista 32/64, Windows 7/ 32-64