My last character died and I wanted to create a new one using all the available rules so I finally subscribed to DDI. Wanting to get rid of clutter on the table I decided to pick up this app. While it is not perfect, it is very useful and has many of features that replaces the paper on the table. It doesnt upload descriptions from DDI (due to copyrights I believe), but it doesnt take too long to review everything for accuracy and type in the descriptions. Being able to identify used powers, healing surges, damage taken, etc and knowing whether you used them in the last session is great. And you can reset used powers with a simple short rest or extended rest button.
The only big downside that I see is for changing a character (new equipment, leveling up, etc). You have to manually do it in the i4e software because if you use DDI to make changes and import the character in you will lose all of the information that you had to manually type and will have to review everything again to make sure that it is accurate.
Taysir about i4e