It's a bit on the long side. BitcoinMag.co.uk would be better.
There's unlikely to ever be a real magazine about Bitcoin, only a website or blog, as costs are too high.
There are already other Bitcoin news sites, such as CoinDesk, they tend to name themselves with short and catchy names.
Overall, domain alone, it's hard to see much resale value.
It's one of those projects where the money is in doing it, e.g. creating your own CoinDesk, but you can't expect to sell the domain for it easily, all the money is in doing it.