Things I found on the market:
eZShare
Looks like it represents small web server inside.
http://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l2736&_nkw=ezShare++SDHC
FluCard
http://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l2736&_nkw=FluCard++sdhc
Name make me more pessimistic about it. Seems similar to first one.
Eye-Fi
http://www.ebay.com/sch/i.html?_nkw=Eye-Fi+&_sacat=0&_odkw=Eye-Fi+Connect+X2&_osacat=0&_from=R40
As I understand any X2 will do.
What will be best for fast photos upload?
Photos must be instantly transferred to smartphone. Resized to normal resolution. After this you need ability to select them and instantly post on twitter with short descruiption.
No one uses wireless cards?
This looks interesting...wondering if there are any faster ones coming like a Sandisk extreme pro but with wifi transfer. When I use gh2 that's all I use because I like your ptool + driftwood GOP 1 settings ;)
My X2 works well but my gx1 shuts transfer off even in standby so I often find myself pulling SD card to card reader when I have lots of photos. EyeFi transfer software recognizes it in reader and still does its job. Android app is good, but still slow.
eye-fi is most popular one, and also cheapest one as far as i can see, which is strange.
It looks like you're new here. If you want to get involved, click one of these buttons!