Here's the situation. I have a 2010 MBP 15" with the 2.66 i7 in it, 500GB stock 5400 rpm HDD, and 4GB of RAM. It has been slowing down but after Yosemite, it has gotten real slow (and the OS looks like crap IMO. I feel the OS really is designed for Retina). I'm currently debating my options. I could look at upgrading now (or soon) to the 15" rMBP with the 2.5 i7 and dedicated GPU or I could upgrade the RAM and upgrade to a SSD in my current MBP from Crucial for about $300 for a 512GB SSD and 8GB of RAM and wait for Skylake as that sounds like a major upgrade. I'm not sure if it's worth the cash to keep it going given its current resell value is around $500 but then again, I don't know when we will see Skylake (or what Skylake will really bring).