Recently, my household has obtained and utilized both an iPad and a Droid tablet (ASUS Eee Transformer Pad). Here are some brief comments based on my experience thus far…
As far as my experience goes, the most reliable tablet has been the iPad. Trust me, I am NOT an Apple enthusiast. I switched from an iPod to a Zune after using an iPod for close to 3 years. Microsoft continues to amaze me and I am excited to test out Windows 8 as soon as I have that opportunity. With that being said, I have never ever experienced an application crash with my iPad.
The ASUS Eee Transformer Pad (Droid OS) had application crashes 95% of the time I used the tablet. I recently gave the ASUS away (for free) because I didn't want to throw the thing through the window (or take out my frustration on it like what happened with my HP TouchSmart TM2T - long story).
The major problem with tablets that are not iPads has to do with App Stores. Apple is extremely picky when it comes to approving applications for availability via their App Store - extensive testing is performed on these applications. This is why iPhones and iPads have reliable application/OS performance.
Microsoft made an extremely intelligent business decision with the recent Windows Phone 7 platform by introducing a stringent application marketplace that will not allow just any application onto the marketplace. Microsoft has a detailed performance testing and baseline standard testing certification process that applications must go through prior to being made available via their marketplace. This is the smartest move on Microsoft's part and rumor has it that Windows 8 may have a similar marketplace for its tablets. These Windows 8 tablets will be the only true competitors to Apple's iPads.
Available applications on specific marketplaces are also a major part of consumer selections. Just because WebOS tablets look pretty does not make those tablets true competitors to iPads - a lack of Angry Birds could drop and divert sales of tablets in an instant. The best tablets have an abundance of both business applications and leisure applications.