Personally, unless there's some massive gas price increase or oil shock/gasoline shortage, I think overall US plug-in vehicle sales will continue to muddle along in 2013. I have no idea if that increase or shortage will happen.
I'd guess that for CY '13, the Leaf will probably sell no more than 12K units in the US, 18K tops. I wouldn't be surprised if it doesn't get past 10K.
Judging by http://www.hybridcars.com/december-2011-dashboard-sales-still-climbing-35093/" onclick="window.open(this.href);return false; and http://www.hybridcars.com/november-2012-dashboard-65420" onclick="window.open(this.href);return false;, US Leaf sales averaged 806/month in 2011 and 694/month in 2012. Even 12K/year is already a 24% increase over 2011, which was the best year so far but we've got more and more EV and PHEV choices now.
If we do have the above massive gas price increase or severe oil shock, then my numbers would be too low and I predict Nissan really cranking up production and passing 15K units/year in the US. Even in about the worst gas price increase ($8/gal) and oil shock (embargo, rationing, etc.) case I could think of for '13, I don't think Nissan could move more than 70K Leafs in the US in '13.
'13 Leaf cost? Perhaps we'll see '13 SV and SL prices go back to the '11 level of MSRP of $32,780 and $33,720, or maybe even $1-2K less than those. My wild guess is that the lower trim model (S?) will be $2K below the SV trim (or whatever the middle trim level is called).
All these numbers are OTOH, only referencing some prior #s, w/o much in the way of calculations.
I know almost nothing about the i3 as I don't follow it, but I doubt it'll start for less than $35K, just from glancing at starting prices of BMW-branded ICEVs. No clue as to how many it'll sell and when it'll even start sales, but I doubt it'll reach PiP, Volt annual sales or sell at an average monthly rate even 1/2 of the plug-in leader, whatever that is. BMW simply doesn't sell many cars in the US vs. the Detroit 3 or the top 3 Japanese automakers (http://www.autoblog.com/2012/12/03/november-2012-storm-surge-edition/" onclick="window.open(this.href);return false
.
I predict the Accord PHV will sell very slowly and probably will have a monthly sales rate of 1/4 of the PiP, if not worse.
I believe the compliance cars Spark EV and Fiat 500e will sell in tiny numbers and only get sales that are 1/6 or less that of the Leaf in terms of avg. monthly sales rate.
I predict that in the US, PHEVs/EREVs overall will still outsell pure BEVs.
I predict Coda will go banrkupt in 2013 and we'll continue to see Fisker not do well. I think the chances are pretty high Fisker will go under in 2013 as well.
I doubt we'll see widespread deployment of Frankenplug (J1772 combo plug) stations. Perhaps where new CHAdeMO stations are being deployed or where they're being upgraded we'll see stations w/Frankenplug and CHAdeMO. I doubt there will be more than 25 Frankenplug stations in the whole US by end of 2013, if even that.
The Tesla prediction's a toughie. I'll have to think about it more.