half a hour for every person who gets on the train, an hour for a round trip and presuming people get HS2 instead of slower trains it frees up rooms on alternate routes.
Currently though, with the Birmingham to London train routes, you've essentially got two options, on the existing West Coast Mainline.
Either you take the London Midland service, which thousand of commuters do (as I myself used to), it has some trains from Birmingham that only stop at a few stations on the way to Euston, but also those which stop at every station.
Otherwise, if you want to get there quicker and can afford to pay more on your daily commute you can travel by Virgin Trains into Euston.
Now, with this new HS2 service, it's going to be priced higher than the Virgin service, as it's even quicker. Therefore, only those who earn a very high wage can afford to use it as their daily commuter, which is why you can see where the comments about it being a train for the very 'rich' come from.
What will the knock on effect be?
Well if some of the Virgin passengers move to the HS2, then that will free up some space on the Virgin trains. However, Virgin is unlikely to want to drop their prices, which is the only way they are going to be able to get people using the London Midland service, which is by no means cheap as it is, to switch to them.
If anything it could just mean even more people commuting into London, so it's not doing much for capacity and rush hour overcrowding.