You'll likely be spending $650+ for a decent gaming PC. Most things below that aren't even up for consideration for gaming.
"Next gen" on consoles doesn't mean much for PCs.
PCs are, and have always been, far beyond the capabilities of consoles.
"HD"? My
Windows 98 computer did that shit in Quake 2.
Anyways as far as planning for the future, I'll quote a friend.
Rapid obsolescence:[/b] PC hardware becomes out dated VERY quickly. If you spend $7000 on a computer now, in 2 years time (possibly less) you could build a computer for $2000 (possibly less) that would handily outperform the $7000 system. It would be MUCH smarter to build a completely new $2000 computer every year for 3 years than spend $7000 on one computer and expect it to last you for 3 years.
So buying hardware for the future isn't a good idea. Buy hardware for the now.