You're welcome. If you find with the Wired connection, Steam slows the entire FiOS connection down a little bit while downloading, that is expected as Steam uses servers very close to the "last mile" and also multithreads downloads. If it becomes unbearable, which it shouldn't since the downloads should finish up quickly on FiOS rather than take a whole day as it does for me (I'm on DSL, 5Mbps), Steam has a built-in rate limiter that can be used to control the download. I've got a few folks here besides myself who also use Steam, and on top of all of the YouTube HD, Ventrilo, video and gaming traffic, bandwidth gets pretty tight here. Can't wait until FiOS shows up here.
Here's where the rate limiting deal is. Like I said, FiOS should download stuff fast enough to not have to use it. It's intended more for slow connections.
Let us know if you need any further help.