I was looking to buy a Pentax K-5 in the next couple of months. But with the announcement of the new K-30 im now currently questioning that decision. Is there any reason to go for the more expensive K-5 apart from an extra 1 fps over the new K-30?
As you can see from a side-by-side feature comparison, the K-5 has a few advantages — 14-bit processing, somewhat faster shutter, a few more modes on the dial. It has a top LCD screen, and it has a magnesium-alloy body. On the other hand, the K-30 has some improvements of its own. Whether these things are compelling to you is a personal decision, but as Digital Photography Review says in their hands-on-preview:
... we can't imagine Pentax expects to sell many K-5s once the K-30 reaches shop shelves.
The K-5 is basically over as a new model, and of course the speculation is rampant on what will replace it. Pentax will surely release something at the K-5's former over-$1000 price point *, and given how exciting the K-30 looks, that will be another hard decision all over again if you wait another few months. (Waiting for that is not my recommendation — my suggestion is to buy a camera and start using it, as the advantages of a real camera in the hand beat two fantasy cameras in the bush every time.)
You may want to consider a used K-5 — it's likely a lot of those will be coming on the market as the technology-generations dance plays out, and the close comparison with the low-priced K-30 will probably mean those are quite affordable. You might even go for a used K-7, which has most of the same features but an older (capable but more noisy) sensor, and spend your budget on lenses.
* I'm leaving this as-is because it's inherently a point-in-time question, but for what it's worth, the K-3 replaces the K-5, and now the rumor mills are on to speculating about what might replace that. It's a never-ending game.
As a former Pentax K-5 user, I can tell you that it has better video quality than a Pentax K-S2. The reason is that it uses older compression with a much higher bitrate and shake reduction has fewer axis "motors" (linear motors).
What about the K-30? I'm not sure, but I think from that model Pentax changed the compression and bitrate.