NO NO NO NO NO! Please don't let this happen, someone! Acer is HORRIBLE. Asus products are nothing short of awesome, it's not just the quality (which I have no complaints about whatsoever), it's the amount of features their products have for the price. They're almost the only name in consumer wireless networking right now, with Intel closing down their motherboard business there's just no one else left in the motherboard business and their ROG laptops are the pinnacle of affordable mobile gaming. Acer is a pile of cheap pushover garbage that people buy because they don't know any better.
Asus and Lenovo? Lenovo is the same junk as Acer or worse at times, their low-end offerings disgust me, the ONLY good thing about Lenovo are their ThinkPad keyboards and *nothing* else. I wish that they, along with HP, Acer, Gateway, eMachines and all other low-quality brands would crumble to dust - sadly, that would severely reduce the competition and mess up the market. But at least don't have any of them merge with Asus! There is NOTHING Asus would get from that deal! Acer has no production lines, no [significant] IP, no significant product series (their junk gets phased out in favor of newer junk quicker than you learn all of their horrible naming conventions). Asus has their own production, ought to have some interesting IP AND a ton of significant products - their motherboards, their networking, their ROG laptops...
If Asus knows what's good for them, they won't do it. They are JUST starting to become well-known (it's their own fault for not advertising enough for so long) and they can NOT afford to taint their brand name with low quality of Acer. Buy their stock, do some other stuff, but DO NOT MERGE.