Do I need a tablet

Pros of a tablet:
Usually excellent battery life as compared to a laptop
Instantaneous boot (I know laptop that are beginning to rival this but they are not nearly mainstream)
Portability / Weight
Simplicity - Very few OS hassles (and if there are just factory reset)
Cloud Connectivity - documents, address books stored on a server somewhere so when you lose the device you buy a new one and most of your stuff comes back.
Works faster outta the box - I'm not worried about giving it to grandparents or the three year old and they press some button and I don't know what happened (well mostly not worried... they can still drop it).
Several hundreds of free / low cost software (apps)
Account driven purchasing of software - no more losing discs and product keys.
Low amount of malware/viruses for IOS/Android/WinRT and curated gardens by those companies to keep you safe.

Cons
No keyboard - typing on them is pretty terrible (I know you can buy a seperate keyboard but I don't like buying accessories)
Semi terrible printing - printing support is pretty bad (I would say only good on the full windows tablets)
Semi terrible media creation - (I don't see many people running about with their ipads creating docs in pages)
Connections with other devices is iffy at best... will generally work with some type of adapter that is not sold with the device.
Small storage space.
Without internet connectivity your experience will probably be pretty poor
Terrible repair-ability - you break it you're most likely buying another one not fixing it.
Remote nuke - companies have control to take content back out of your device even disable the device entirely (although unlikely there is precedence for such occurrences).

Other Notables
They seem to make you forget your other devices - you ever watch a person taking video or a picture with their ipad.
Execs will say they are the greatest thing ever but all I see them do is present a picture slide show. I can do that with a photo frame.