A quick series of observations:
1) It is highly likely that LTE will have to be provided (at least in part) by femtocells and/or WiFi access points, rather than being solely transmitted via the macro network. This will be for coverage reasons, especially for 2.6GHz, but also because of the limits of capacity which will be quickly reached in some areas.
2) Given rising traffic volumes, there will also be a strong desire to offload bulk IP traffic direct to the Internet close to the edge of the network, rather than backhauling it all through to the operator core & then out again
3) Voice will in some packetised form on LTE, whether it's VoLTE or VoLGA or Skype or CSFB.
So... there will need to be a mechanism to send VoIP to the operator core, but dump bulk web traffic locally. I guess that could be achieved by using separate APNs (or whatever they're called in LTE-speak).
Or, will it need the new "Selective IP Traffic Offload" standard being worked on by 3GPP?
Or, could you use some sort of dual-radio solution in handsets, sending certain traffic over the macro LTE network (or HSPA), while sending low-value data via WiFi / femto?
Separately... presumably this also means than any VoIP that *does* go via an offload path (femto / WiFi) will need to be tunnelled back to the operator core via some sort of VPN.
So potentially we may see some LTE phones using CS-Fallback over a GAN-type tunnel.....