I am currently looking at the Intel Core i5-4690 Haswell 3.5GHz LGA 1150. Is this a reasonable upgrade or should I wait for broadwell to come out? I feel that if I keep waiting for the latest and greatest, more just comes out shortly afterwards. Is this new 4th Gen processor good for a few years? I like playing games like ARMA III. Thanks for taking the time to read this. Sorry if it vague. I am so overwhelmed with computers!
If your Sandy Bridge motherboard is either a H61, H67, P67 or Z68 chipset, then you can upgrade to an Ivy Bridge processor (3rd generation.) I'd recommend the Intel Core i5-3570, as it performs somewhat similarly to the Core i5-4690 you desire. If you go for the i5-3570, you won't need to upgrade your motherboard, as it is compatible with your current motherboard/chipset; however I'd double-check your motherboard's manufacturer's CPU support list just to be on the safe side.
If you don't have any of the above chipsets mentioned, then you're stuck on Sandy Bridge and will need to replace your motherboard for any future generation CPU support. At this point you may as well get a Haswell motherboard with your desired 4th gen CPU.
If you do go for the i5-3570 upgrade, it actually is still a great processor, and tied in with your graphics card; you should be able to play most games at full graphical settings. Personally I think the Sandy Bridge motherboard's are still viable, even more especially those with Ivy Bridge support.