There are trade offs with a premium tank so the decision to buy one is not as simple as saying 'does it make more money?'
Firstly a premium tank is costly to purchase, the high tier ones with the best earning potential are 7500 to 12000 gold (£30-40) each and there's no point in buying a premium tank without spending another 1000 gold on a 100% crew, you will also need to spend another million silver (2500 gold) to get Ventilation and a Rammer. So that's a layout of approximately £50-60.
Secondly you need to know that the premium tanks are not the best tanks (apart from the Type 59 of course). An equivalent tank of the same tier will generally out perform a premium tank by a small but appreciable margin.
Thirdly, for grinding out silver a premium account effectively doubles your income. Although it only boosts your basic income by 50%, that is before you pay for repairs and ammo which can easily halve your final income, but with premium that 50% bonus to the gross amount works out as about 100% on the net profit. Premium tanks only have a significantly reduced repair cost which is why they're good for grinding silver.
Fourthly you need to be at least an average to good player to really benefit from a premium tank, just turning up and going AFK in a premium tank is only minimally more effective than doing the same in any other tank. You quality of play massively influences your income.
So yes, premium tanks can earn more money, but it's no as simple as buy premium > profit!
Best Answer
Updates will be much more frequent on the PC than Xbox 360.
For example wargaming are going through all the tanks overhauling their textures and have made several big changes to maps recently.
In order for these kind of updates to be applied to the xbox version, each one would need to pass a number of certification tests.
This was the problem with the console version of Team Fortress 2 and as a consequence the Pc and console version became so different you could no longer compare them.
The console version does have controller support which is a nice thing that the PC does not have.
With the PC version you can install mods and customise how you HUD looks and display live stats to help you when playing the game.