I have the Medtronic Paradigm MiniMed Pump and LOVE it. I've looked into most of the other options when I got the pump (which was about 7 years ago now, wow!), and I've looked into the OmniPod in depth. I loved the idea of the OmniPod because it can be attached more places than the minimed, but I've talked to users who both love it and hate it and there are a few things about it that I wouldn't like to deal with, including the limited reservoir, you can't move it once you place it (for different outfits, for instance), and a few other things. The MiniMed is extremely user friendly, which I love, and it has a few different options for kinds of cannulas you can use to place it.
When I was looking for my pump the animas (one touch system) was much less advanced than medtronic, but I can't speak for it now. I've looked at the Ping, and I haven't seen anything that the MiniMed doesn't do - my meter automatically communicates with my pump and my pump (with the preset settings) knows how much insulin I need to adjust for my numbers and how many carbs I'm having, and I could have a remote if I wanted it as well.
I've seen a little about the Accu-Chek, and again, haven't seen anything the MiniMed doesn't offer. The MiniMed is waterproof for accidental exposure, and connects to a PC (or Mac) via USB and provides tons of charts/data with numbers/insulin/etc.
If I didn't have a pump now and were to get one, I'm not sure what I'd do... I think I'd look closer at the Accu-Chek, but Medtronic has always been so far ahead of the curve as far as advancements in the medical field and with research I would find it hard not to have a product that I know will be consistently on top of its game. That includes benefits with insurance; Medtronic is highly trusted with insurance. (I also received a free upgrade of my pump after 4 years, and the MiniMed has a 4-year warranty, which I've used - I just had a crack on the screen I didn't like and they sent me a new one! For a $6,000 pump that's pretty awesome.) And Medtronic's customer service has always been amazing, available 24/7.
I just realized I sound like I work for Medtronic... lol... but I really don't. I've just had my pump for 7 years and have only had 100% positive things to say about my pump and Medtronic, which says a lot. Plus, I keep up with Medtronic and the things they're doing as I'm an RN and am especially interested in their research!
Hope this helps a little, and although I am very biased toward Medtronic, you should definitely consider all your options and look at what your insurance will cover, overall price, how much insulin you use (different pumps hold less/more insulin), etc. I would make a list of your priorities and look at the pumps that fulfill them the best! Have fun choosing!