We had a chihauhau who hated the water but that was great for the boat as we've seen water loving dogs get in trouble jumping in where they shouldn't (ie: they got out of the cabin while owners are away and the marina doesn't have a place for the dog to climb out on thier own). Otherwise, he was very happy on the boat or in the RV.
Living aboard: Of course our whole point is to travel but we've been stationary at times for 3-6 months. Never been an issue. We haven't been on the west coast but outside of Florida & Georgia, no one seems to care. Even in those two states, as long as the boat is well kept and you aren't living there for years, they never made an issue of it. We do usually stay in a slip but it's somewhat price dependent. In really expensive areas, we tend to anchor out more but if you ask about monthly rates, it's usually not too bad ($250-700/month).
Long term: We've been at it since 2007 and have no plans to stop.
The nice thing is RV's are a lot cheaper than boats. Our current setup which we bought in 2009 has a total of $10k ($6k for the truck and $4k for the 5th wheel). For $20-60/month, you can store the RV in a lot in most areas.
Another alternative we've played with recently is destination apartment rentals. We spent a month in Mexico and 3 in Italy last winter.
Blog: I haven't been good about keeping it up lately but the link is below.
valhalla433.wordpress.com