Once personal terms are agreed, forward Demba Ba will join Chelsea. I was initially somewhat sad about this - I've always liked Ba, and thought he'd be a useful piece of depth for Arsenal, but then I read that he has several agents, all of whom will get a piece of his transfer fee and all of whom created and inflated the market for himm (there are reports of seven-figure transfer fees for multiple agents). Ba also has a knee that could charitably be described as "delicate", so all in all, while a Ba-type player would still be a nice pickup for Arsenal this month, I'm not despondent over missing out on Ba in particular.
Arsenal, of course, remain very tight-lipped about potential targets; this is nothing new and should not be construed as "Arsenal aren't doing anything". It's early in the month. As usual, we'll keep an eye on the internets and if anything starts to look, feel, or smell like an Arsenal transfer, we'll be all over it.