Yeah, wonder what's taking them so long with supreme pokepuffs and wardrobe clothing though.
It's most likely either one of these two reasons. Either they already know how to do it but are holding them back mainly so that they will have things to roll out in the future, or they are waiting for others to do the grunt work and then capitalizing on it.
I can see either one being possible. There is so much hype generated by this device for Pokemon that it would make sense to hold back some content to roll out at a later date. Look at this thread. Everybody sits by their computer each day to see what Datel will roll out next. If they released everything at once, that would greatly reduce this hype and potentially effect sales. Constant talk and chatter drives sales and anything that would potentially decrease this could be seen as a marketing threat.
I can very much see the other option as being possible too. Coding and code discovery takes time. It also takes money. If you can let other people do the work for you for free, why wouldn't you? I'm not saying that it is right or wrong, but Datel is in this for one reason, to make money. Anything they can do to maximize profit, they will do it. Personally, my money is on this reason, but that is only my opinion.
Bottom Line: The reason why it is taking so long is this. Whether it is USD, Euros, British Pounds, Mexican Pesos, or whatever other currency you want to look at, the main reason all revolves around Datel making more of it.