Cat5e will be fine for some time, you can even run 10GBaseT on CAT5e (up to ~40m, which unless you live in a mansion should be good enough).
Where did you hear that? All I've managed to find is that 37m is the max on Cat6 UTP due to Alien cross talk so can imagine Cat5e will be significantly less especially if terminated poorly/cheap cable. I have read some articles that certain manufacturers making 10GBASE-T switches will allow upto 40m on Cat 5e in perfect conditions, but then hardware costs would be very high.
But for 1000BASE-T Cat5e should be fine.
Personally looking at sticking in Cat 7 into my girlfriends place.. come down a hell of a lot in price lately and for me, now is the time to run cables as Im not going to have access again to certain places. Last time I checked Cat 7 was about £600 a kilometre, which considering top grade (Krone) Cat5e UTP is £60 and STP was £125 for 300m, it's about 4x the cost but more than 5x the bandwidth.
But really depends on length of time you envisage on living in a place, and how much of a pain in the arse it is to put new stuff in, if you're that way inclined. Especially when you want to distribute Full HD signals around your home aswell as CATV, certainly make life easier when one cable does all.
But anyway, will wait to get shot out of water, but I am intrigued to know where you found that info Hazard, could be interesting read ( sad I know

).