When new tiles are downloaded they flicker for a while. See gif record. (In real the flickering is faster, but this is not captured by the gif.)
Also the red cross previously was only displayed, if there was an download error and not for tiles, which are not yet downloaded (There was the hourglass icon). This was much more friendly.

Revision: 8175
Repository Root: http://josm.openstreetmap.de/svn
Relative URL: ^/trunk
Last Changed Author: stoecker
Last Changed Date: 2015-04-07 10:18:15 +0200 (Tue, 07 Apr 2015)
Build-Date: 2015-04-07 08:40:02
URL: http://josm.openstreetmap.de/svn/trunk
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last Changed Rev: 8175
Identification: JOSM/1.5 (8175 de) Windows 7 32-Bit
Memory Usage: 671 MB / 742 MB (228 MB allocated, but free)
Java version: 1.8.0_31, Oracle Corporation, Java HotSpot(TM) Client VM
VM arguments: [-Djava.security.manager, -Djava.security.policy=file:C:\Program Files\Java\jre1.8.0_31\lib\security\javaws.policy, -DtrustProxy=true, -Djnlpx.home=<java.home>\bin, -Djnlpx.origFilenameArg=C:\Program Files\josm-latest.jnlp, -Djnlpx.remove=true, -Djava.util.Arrays.useLegacyMergeSort=true, -Djnlpx.heapsize=256m,768m, -Djnlpx.splashport=60630, -Djnlpx.jvm=<java.home>\bin\javaw.exe, -Djnlpx.vmargs=LURqYXZhLnV0aWwuQXJyYXlzLnVzZUxlZ2FjeU1lcmdlU29ydD10cnVlAA==]
Program arguments: [--debug]
Dataset consistency test: No problems found
Plugins:
- DirectDownload (30892)
- DirectUpload (30892)
- HouseNumberTaggingTool (30892)
- OpeningHoursEditor (30962)
- PicLayer (30962)
- RoadSigns (30977)
- Tracer2 (30984)
- buildings_tools (30955)
- download_along (30892)
- editgpx (30892)
- imagery_offset_db (31056)
- measurement (30892)
- mirrored_download (30962)
- photo_geotagging (30967)
- photoadjust (30964)
- public_transport (30892)
- reltoolbox (31056)
- reverter (30990)
- tag2link (31066)
- terracer (30892)
- turnrestrictions (31034)
- undelete (30892)
- utilsplugin2 (31072)
- wikipedia (31035)
Last errors/warnings:
- E: Defekte Objektvorlage "bla-Type" - Anzahl der Datenworte in 'display_values' und in 'values' müssen gleich sein
- W: JCS TMS Cache - error creating URL for tile 15/17550/11011@Bing Aerial Maps: Attribution is not loaded yet
- W: No url returned for: 15/17550/11011@Bing Aerial Maps, skipping
- E: Skipping to the next rule, because of an error:
- E: org.openstreetmap.josm.gui.mappaint.mapcss.parsergen.ParseException: Encountered " <REGEX> "/^addr:/ "" at line 10, column 5.
It is a new phenomenon, I assume it is related to #11216 ?