Useful facts about Overlord Speed Increase (yes I tested this)
ZvT Ohana: Now will barely be safe to send 1st overlord directly to the safe spot behind opponent's natural geysers.
ZvT Korhal Compound: Not only will you now safely reach the cliff above enemy's natural expo, but you can also first quickly peek at their wall-off above their ramp before retreating to safety
ZvT Daybreak: You will now be safe to send your 1st overlord to the space (or those high up, blue box things that also hide your overlord) behind opponent's natural geysers.
ZvT Cloud Kingdom: Now more than enough time to safely reach the cliff above their natural. If you wanted, you can also send it straight behind their main (that large area behind their gases). The only reason I guess is to either check their gas timings or suicide into main to spot build (suiciding now scouts more too).
ZvT Metalopolis: You can send your first overlord to check if he spawned close by air, then if he's not there, you can send it cross-spawn, in that large airspace behind their main and still be safe.
ZvZ Antiga Shipyard: Sending your 1st overlord to either of the close mains, if you found him you can now spot if they went an early pool before you place your 15 hatch down. Then just plant a pool instead and you're ahead. Also FYI sending a drone right at 9 supply to the other 2 locations, as long as you go only halfway up the ramp for the first base you scout (to peak if there is creep), even if they were cross spawn your drone should scout an early pool just before you place a 15 hatch.
ZvT Antiga Shipyard: Send your first overlord cross spawn directly to the space behind the natural minerals and it'll arrive barely in time to be safe, while also glimpsing their wall-off. This is mostly useful for tourney versions where they're cross only, but it's nice on ladder too because it also scouts the center for any proxy raxes, and it feels cool. Also you can send your 2nd overlord to the clockwise spawn if you think they're there, to the same spot behind natural and it'll be safe. Unless you want the 2nd to always scout your own natural for bunkers.
ZvT Shakuras Plateau: Send OL close-by-air, if you see him there, keep going floating over his base, check his wall-off above his ramp, then go to the airspace on the other side safely (so you can check his natural later easily). Where Queen Range 5 will be most useful:
Queens will sit further behind your army when defending attacks, in a safer area. It will be noticeably easier to keep them alive.
1 queen will be able to kill a scouting worker than runs right by the queen now! (if the scout tries to skirt around the queen it should survive, provided it's not at a choke) Also of course it will be harder to fully scout for what buildings zerg's made.
Players may sometimes deem it worthwhile to get a couple more queens than normal for defensive purposes. Why? 1 Queen does more dps than a stalker (provided that unit has 0 armor. Armor is twice as effective vs the queen's 2xAttack, and queens attack fairly quickly), and with 5 range + the ability to tranfuse and spread creep, players may want to get a couple extra before they really get their army production going. Just note that since kiting with queens is pointless and they're molasses off creep, and their dps drops quickly vs anything with Armor, they're not going to really be a great fighter unit in your army comp, and since they pose almost no threat for an attack, units will often be the preferred choice. Unless you nydus into their base
(probably not worth reading
The unique situations where you built many queens to defend vs air, and you didn't take much damage, and then decide to counterattack because they're vulnerable (often they are depending on their air units to keep them temporarily alive, which is where your queens come in). Well now if you attack with army + queens, queens will probably hit ground stuff now too. ZvT:
Queens will be quite a bit better at pushing back a hellion 'contain' (so you can safely spread tumors)
Will help defend bunker rushes (attacking scvs building bunkers, marines).
Hellions (range 5), marines (5), and reapers (4.5), will no longer kite queens without taking hits. They will just generally be better at dealing with most terran units as they are no longer outranged by most of them. ZvP:
Stalkers (range 6) harassing queens will be slightly easier on the zerg
Defending zealot harass slightly better
Very situationally help vs cannon rushes (particularly the 3 pylon wall below ramp can be safely hit now by a queen. It takes exactly 1 ingame minute for a queen to kill 1 pylon.)
Just generally be a little more useful at fending off early rushes or small attacks. ZvZ:
When you've 2 queens blocking ramp while lings attack your spine/s, now your queen can often attack back while standing there.
Better at denying baneling run-bys
A bit better at dealing with ling harassment
Hatch-first builds in particular will be slightly easier to do/better than it is now.
Situationally vs roaches (queens will outrange them), like when they're on hold position behind your mineral line when they went around your spines.
Some zvz timings involve roaches/queens/infestors (usually vs muta builds) so they may be marginally more useful there (though they're mostly for antiair and transfuse still). Did you know?
Queens do 8 damage to ground, but it's split into 2 Attacks of 4 damage each, so Armor is twice as effective vs queens. But more importantly, the attack animation to do both attacks is so long that there's essentially no time to move in between attacks. If you try, you'll just end up delaying the next attack and doing less dps. So basically, don't try to kite (move in-between attacks) with queens, range 5 or not, doesn't matter. (technically you could kite a zealot  but it's not worth it.)
HOWEVER when Blizzard changes the look of the attack animation like they said they would, this might change. But logically, assuming they just make the tentacles look longer, it would either stay the same or be even slower (worse!).