I've also noticed the explosion in the House Sparrow populaton in my garden. A welcome sight (and sound) over a few years ago, when there seemed to be only a couple of pairs in the garden.
Over the last 2 weeks I have seen a Kestral regularly fly, at head height, through the garden. Obviously looking for any stragglers. Yesterday the Kestral actually landed on the apex of a neighbours single storey roof extension, 10ft away from the bird feeders and where the sparrows had been feeding. What a noisy warning sound they made too.
One new arrival to my garden has been a flock of Long-tailed Tits, who have become a regular daily feature. This has brought the count of different Tit breeds to visit the garden to 4. They are such a joy to see and hear.
The strangest visitors so-far to the garden, happened earlier this year. When I got up this one morning I found 4 mallard ducks, heads tucked under their wings, having a kip in the middle of the lawn.
With the increase in our garden birdlife populations, one thought that has crossed my mind and no doubt others too. That is, the need to ensure that we continue to regularly feed and supply fresh water for our garden wildlife during this forthcoming winter period. Hopefully this will help to maintain the bird population for next year.