I'll give this one a stab.

At the moment, it's not going to change anything. IPFS looks to be a solution looking for a problem. Basically, it's a shared global data store... You share a number of image/text/video files to IPFS, and those files are replicated to all other nodes across the IPFS filesystem. You can can then access those files both locally as well as from other people's sites.

There's no real provisions made for dynamic sites (e.g. php). If you had a php-based site then it wouldn't work like you would expect it to (not every node in the cluster would have PHP), likewise, as a node owner, you wouldn't want third party scripts running on your system due to security. Let the right script get run and your node is now compromised.

Speaking of security, there's no real encryption at the moment. There might be transmission encryption via SSL, but that's it. The datastores aren't encrypted.

Let's accept the argument that IPFS takes off and lots of people buy into it and start uploading photos, documents, whatever to IPFS. You have to realize that every other node will receive a replica copy of the full files. So, your 1MB of pictures and shared documents turn into terabytes of replicated network data as everyone else receives a copy of it. Your own local store will swell with copies of everyone else's data.

Finally, it just takes one asshole with some kiddie porn to turn a whole bunch of computer geeks into hard core felons.

Note this was from me browsing their site for a couple minutes and watching about 1/2 the demo video. I may not be the expert you're looking for ;)