It's unlikely to take anything like 8 years. Much of Google's effort during that time has been refreshing images of streets they had already visited. If Google has visted a street 4 times to keep the data up to date, Apple only has to visit it once to be just as up to date (and continue to visit regularly after that to stay up to date, of course).
edit: mixmastamyk beat me to it by 1 minute, so +1 to you sir.
That's not entirely true; Google does not refresh all of its data every cycle: some "rare" locations (where few people live) have been visited only once during those 8 years.
To catch up you need to cover all locations, not just the frequent ones, so that takes more than one cycle.
Google doesn't cover 'all locations' so I think that's a red herring. Their best bet is to provide a service with unique distinguishing features that is competitive with Google. Similar or competitive coverage is just one measure of usefulness.
Google refreshes their street view every so often, so if they have a comparable fleet it should take about the same amount of time (roughly 2 years or so).
That's like saying Apple was 10 years late to the mobile phone game. If I have learned anything in my lifetime is that it doesn't matter how early you get started, newer and better technology will make incumbents obsolote. I'm sure Apple's street view is nothing like that of Google, but better.
