A growing trend of poor platform choices. The obvious stuff is that their once great keyboards are now terrible. Mouse buttons are the other one.

On the more hardware nitty-gritty side of things though, nearly all of their laptops the last 4 years have heat problems, including one line that you can never use more than 50% of the CPU before it throttles due to severe overheat. My second-gen x100e is the second laptop I've ever used to actually give me a burn - and from doing nothing more than streaming a youtube video. Their x series are basically unusable and were the only ones I would consider buying to begin with.

Sorely disappointed.

Edit: Also their software is shit, but I don't use Windows on it anyway. They're still better than ASUS laptops though.

Apart from the things other people here already mentioned. The speakers are the worst i have ever heard. I don't have high demands on laptop speakers to start with but this is way below any standards. Music you can just forget about and even in voip calls it's hard to hear what people are saying. And even when they are off they are bad! They keep sending out a faint white static noise, i first thought it's the fan but it's actually the speakers. Lenovos "solution" to this problem was to update the driver and turn off the spekers completely if there's been no sound for the past 5 seconds. Really annoying, any time you open a folder in explorer and the click sound plays it sounds like the fan turns on and then off again, same with intermediate IM notifications, i have to keep my laptop on mute because of this. So the speakers are useless for music, voip and notifications, what usage scenario is left? why even put them in?

Talking about the 440 series: no physical buttons on the trackpad, keyboard changes, a lot harder to take apart, 12GB max memory. It's basically not a Thinkpad anymore but a black MBP wannabe.

They've started messing with the keyboards. I don't find this an issue personally (I'm typing this on a X1 Carbon 2014), but it bothers some people.