According to John Cross of the Mirror, Arsenal has "agreed a deal in principle" to sign Granit Xhaka from Borussia Monchengladbach. It's unclear whether that means the deal with Gladbach is finished, or if the contract with the player is also finalized, but either way it's good news if it's accurate.
According to Cross the deal would be for £33.8 million (around €43 million) which is basically what's been previously reported. It's actually a little less, which is nice – usually the fee inflates over time.
Cross is reasonably reliable, but can be led around by Special Interests (club sources, agents, people like that) at times so it's tough to get too excited about this. But if in the next couple of days we hear something similar from other sources, well, this thing might be on for real. According to the Mirror "Xhaka expects negotiations to be completed within the next few days," so we should probably know more soon one way or the other.